Poloniex or Bittrex
Bittrex is well-respected among the cryptocurrency community, as their team seems to be hard working around the clock. Not only can one reach support via Twitter, but they are very active on IRC too. Most issues with the platforms – such as a wallet needing an update or adding a new coin – is taken care of relatively quickly. All in all, a very professional service.
Poloniex can be classified in the same category,as they are also working very hard to keep the altcoin exchange up and running at all times. New coins are added very carefully, as there are a lot of pump-and-dump schemes to be found in the world of altcoins. Support staff is very friendly, although it might take a while longer to get a reply if the issue is not critical.
Trading fees is what can set most altcoin trading platforms apart, yet Bittrex and Poloniex operate on an identical fee structure. All trades are subject to 0.2% commission, which is relatively normal in the world of digital currency. No fees are associated with deposits- as they are paid by the sender – but a mining fee might be deducted for Bitcoin withdrawals.
While both Bittrex and Poloniex are targeting the same markets, their listed trading pairs can differ by quite a margin. Bittrex offers various trading markets against fiat currency, which Poloniex does not. However, Poloniex offers secondary trading markets against Monero and USD Tether, which Bittrex does not offer at this time. It all depends on what the end user wants to do and feels comfortable with.
Both Bittrex and Poloniex are generating a healthy amount of trading volume across most altcoin markets. Not every coin listed here offers something users will be looking for, but they are still in some demand. It is hard to pick one over the other. as it all comes down to individual preference for trading altcoins. Poloniex and Bittrex have been working hard to become altcoin market leaders in the exchange ecosystem, and they have done a pretty good job of achieving and maintaining that status.
thanks