As of now sp20 is a much better choice by the simple fact that it costs a lot less and you get much better GH/s per BTC, the S5 could be a better choice if the price was right but it is not.
Currently the only point of comparison is the SP20. So consider these 3 questions for a second.
1) Which miner looks like it costs more to manufacture?
2) If Bitmain is not willing to sell at such a low price consistently, is there a reason for that?
3) How sustainable is the more expensive to make miner in the long run?
to answer these 3 questions:
1. it looks like the sp20, but it is really hard to know as a fact, since the S5 seems to use more efficient chips, but overall the case for the sp20 seems better.
The S5 has an S1 design, clearly the S3 design is better than S1 due to better airflow due to the case and due to having 2 fans instead of one, so I would assume that the S1 design for the S5 was chosen to save money and not because it was better, otherwise the S5 would have been based on the S3 and not the S1.
I am not talking about the chips, since it is clear that in each release they are better.
2. I believe they make a good profit at the low price, they probably figure since the BTC price went up, they can make more money by mining themselves or by having a larger margin of profit even if sales drop.
There is a common concept of making a miner barely ROI to maximize its profit, the old concept of how much useful it is for you it is how much it is worth, most asic vendors operate this way, but there is another business concept if it costs X to produce regardless of your benefit it will sell for a small margin of profit as was the case for CPU and GPU miners of the time, as such most high end video cards where always sold out during the early days of bitcoin.
I am certain that as mining becomes less profitable they will reduce the price, proving that the cost to make the miner it is very little compared to the price it sells, not because of all the sudden the miner has lower manufacturing costs.
Of course if the miner did not ROI, sales for them would be very bad, but as long as they can make the money mining it is not a problem for them.
As a rule Bitmain sells the miners in such a way that they will barely ROI. It has nothing to do with the bitcoin price since the hardware cost of the miner which most likely it is in Fiat is well below the sale price, so if bitcoin goes up the price of the miner goes up, if bitcoin goes down the price of the miner goes down taking into consideration the difficulty, if difficulty goes down price of miner goes up, if difficulty goes up price goes down, always making the miner barely ROI.
This is a case of greed, since instead of letting their customers enjoy the quicker ROI, the very low ROI is kept constant so you will always barely ROI, it is not like if Bitcoin goes up in price and then the miner cost more to produce, that is not the case, the fact is that the if Bitcoin goes up in price the price of the miner in Bitcoins goes down since it is sold in dollars, and as such you would have to generate less coins to achieve ROI.
No one will think that if Bitcoin goes up Bitmain will no longer make profit at existing price, the profit for them will be the same, since the cost of making the miner is the same, simply they figure they can get more for the miner.
it is not that they barely ROI due to market conditions, or because of hardware costs, or the price of bitcoin, they barely ROI because it is their business model.
An example of extreme greed is knc, they promised a lot and never delivered, they got the money from customers, lied to them, and once they had the money they build a mining farm for themselves figuring out it was more profitable than shipping the miners to their customers, once they have new tech, they ship the old technology to their customers and very late, so knc basically mine with their customers hardware.
Bitmain is far from being like knc, but the price increase is clearly an indication of greed, we have enough greedy hardware vendors that is the least that we need.
3. as long as there is a profit in making the miner it is sustainable to sell the miner until there is much better technology in which it does not make sense to make the miner anymore, for example today no one would buy a miner that uses 5 wats per GH/s but from the time they were first released they probably had a life of sales of 1.5 years, and greedy vendors took over a year to ship (bfl).
The way mining hardware should be sold in my opinion, not that it is currently sold this way:
1. vendors of asic hardware should not mine themselves it creates a conflict of interest.
2. hardware should be sold like any other hardware, such a video cards, etc, this model was proven to work, as an example this was the case in the GPU days. No video card vendor would say you will make so much mining and therefore the video card will cost more, some individuals did this, but not the hardware manufactures.
The way asic is sold today it is based on your ROI, so the hardware could cost 10 times less, but if ROI is good you pay a premium.
Ironically the best mining days were the GPU days, it was a fair playing field and hardware costs were not based on ROI.
For choosing mining hardware, the hardware that can ROI the quicker is better, and reliability of the vendor is very important, bitmain if they decide to make it hard to ROI for us it is their decision, then it is no good for us, if they wanted us to ROI they certainty could, as of now it appears that spoondolies is more willing to help us ROI, of course as I write this things could change.
if it was not because of the sp20 the S5 would cost a lot more, the opposite is also true if it was not because of the S5 the sp20 would most likely cost a lot more. The miners are not sold based on their costs they are sold based on how much they can ROI, which is wrong especially when it becomes obvious due to greed, also competition is a good thing, and right now there is very little competition.
As an example of this greed I will use bottled water vendors during an earthquake.
in the Asic vendors model.
bottled water becomes a very valuable asset as such it is sold for very high prices, a $1 bottle can be sold for $20 or more since it could save your life and it will sell at high prices, high profits are achieved due to people willing to pay a lot for a product, high volume of sales are not needed, this is a case of greed.
in the case of the traditional hardware sales model like video cards:
water is sold at the same price and it sells out due to high demand, high profit are achieved due to the high volume of sales but not based on greed.
Telephone companies in the old days tried unsuccessfully to implement the concept the more advantage you take of the phone lines the more you should pay, however most people realized that if they were not doing anything special for modems to work there was no reason they should make additional payments to use a modem which they did not provide or did anything special to make it work, and as such their plans to charge more for the use of modems failed.
In the case of the ASICs the less greedy vendors will survive in the end, today no one talks of bfl cointerra, fast hash, or knc this guys were very greedy and they lost the trust of the community.
today we only have spoondoolies and bitmain, and it is a very bad thing is one of this vendors becomes greedy.
no other hardware vendor makes miners that even have a very small chance of ROI.
I am personally planning to buy some mining hardware around march, I will check how things stand by then, but if I had to buy today the clear choice based on ROI is the sp20.
