anyone could review the liquidity swaps i mean both of polonex and bitfinex?
i just really know the advantage and disadvantage both of them
thanks anyway
No experience with Poloniex, but plenty with Bitfinex... here goes...
I don't keep money at Bitfinex on a permanent basis. The rate for BTC swaps (you lend your BTC to a trader who wants to short BTC) is usually pretty low, lower (usually) than the rate for USD swaps (I know nothing about LTC swaps. Hell, I know next to nothing about LTC). Take a look at
the second graph on this page - particularly with longer time frames (12 months to "all time"). You can see the "FRR" (the variable rate) occasionally spikes up high, then very quickly falls back about 50%, then slowly continues to decline (to around 0.0055%). (That's a daily rate, by the way - multiply by 365.25 for an approximation of the annual equivalent).
The way I use swaps is to keep my money away most of the time, watch the FRR, and prepare to pile in some (a fraction) of my BTC if the FRR spikes, and get out once the rate falls to around 25% of the peak. Over time I've achieved an average slightly under 10% annual. Which isn't great, but is way better than I could get with fiat in a local bank, and looks comparable to BTC-Jam.
In my view the risk is less than BTC-Jam - Bitfinex take on the risk. However, there is still the risk that the exchange itself fails, or takes my money and runs.
FRR is variable - if you loan out money on FRR you'll get higher payments if the rate goes up. I don't advise you do this. Everyone does - and the result is there's a metric shed-load of BTC sitting, un-loaned, at the FRR. Instead I recommend setting your own - fixed rate. Take a look at
the top graph on this page and set your rate appropriately. Use low durations at first - two days max. In fact always use low durations unless the rate is exceptional (0.1%+ is my benchmark, but I'm seriously thinking about raising it). Incidentally, that duration isn't guaranteed - borrowers can repay loans early, and will do so, particularly if the FRR is falling and they believe they can get a cheaper loan.
Bitfinex lives and dies on its trading engine - not on swaps, though obviously swaps help with liquidity and keep trading going. However, it does mean that if the trading engine is buggy worry. Their trading engine looks to me to be buggy as hell. Compare BTC/USD rates at Bitfinex with other exchanges, and you'll see a serious disparity during the crash a few weeks back - most exchanges stayed above $200, 'finex went well below. That's probably largely due to margin calls, but while the crash was happening there were multiple reports from traders about trading issues and withdrawal issues (to be fair, I had no problem withdrawing - I think only traders were affected). I started slowly withdrawing all my remaining BTC at that point, missing a large spike in the FRR a few days later - c'est la vie, and at least I still have my BTC. Bitfinex is still in beta (like everything online these days), but they are backed - apparently - by a registered company (mind you, wasn't Enron a registered company?!)
tl;dr: the return isn't great, there is a risk of the exchange failing, and to get the best rates you need to proactively manage your loans. However, you don't need to worry about collateral from the counter-party - Bitfinex do that for you. Is it worth it? I don't know. I kinda suspect I'd have made as much if I'd invested the same amount of time playing with faucets. I strongly suspect that if I'd spent the time earning fiat I could have bought more BTC instead.