You have to do the legwork to decide which miner is right for you.
As far as profit, currently all miners as well as cloud mining is unprofitable. If you read the forums you will see complete and detailed explanations of this.
Thnks DrG, will have a look in the hardware forum. Was not aware that this information was there.
Brian
Brian, you might also want to state how much you're willing to invest and potentially lose. Basically what's your current budget and are you willing to re-invest in more hardware to keep up with difficulty jumps.
Also, you'd probably want to state what's your current electrical costs. Mining at home is essentially dead, especially if you have costs over $0.10 k/WH.
Make sure you read over Dogie's guide like DrG said, but also if you're small timer or home miner investing say $1000 or less, know going in you'll never make that $1000 back. If you accept that going in, then you're just mining for fun, education, and hobby. If you're looking for ROI or profit, you'll need free/cheap electric and need to run something like this:
Actually there is no guarantee of not making back fiat ROI. Say he spent $1000 on 2 S3s (Batch and some PSUs. Say it mined back 1BTC. If BTC stays at $400 the yes he's down $600 (and only has a PSU to show for it). If BTC goes to $5000 per coin then he will have made $4000 profit (5k-1k) in fiat. Of course why bother mining - he could have easily bought 2 BTC today, not mined, and then he would have $9000 (2*5k - 1k) profit.
So fiat ROI is definitely possible but mining doesn't make sense financially since buying coins right now is a better investment. This may change in 6 months.
You're absolutely right, DrG! It is possible with a fiat price spike of Bitcoin, and if he purchased it with fiat.
If say Brian charged it or paid cash for those miners, then yes any spike up in value that exceeds his initial fiat investment is considered profit. But, if he bought $1000 worth of BTC, then bought the miners for 2 BTC, say in this forum in the "Goods" section, then he'd probably wouldn't mine that 2 BTC back. That's the only point I was trying to make, the BTC in, BTC out argument of ROI.
Otherwise, I agree 1000% will all your points.