I like Poloniex and have been using it for several years.
A few years ago it was hacked and there was a big huha here on the forum about it. I supported the Italian guy that runs it, (I think he still does but not 100% sure), in the long thread about the hack, because he showed every sign of being a trustworthy individual, and I was proved right.
I left the Bitcoin scene for a while and when I came back to Poloniex after a couple of years of not logging in there not only did I find a substantial balance sitting there waiting for me, but also that a couple of the "shitcoins" that I had bought just for fun were now worth a lot of money!
I don't think either Poloniex or Bittrex is going to take your coins and run away with them, so it's really down to your personal preferences. Mine is generally Poloniex.
A few years ago it was hacked and there was a big huha here on the forum about it. I supported the Italian guy that runs it, (I think he still does but not 100% sure), in the long thread about the hack, because he showed every sign of being a trustworthy individual, and I was proved right.
I left the Bitcoin scene for a while and when I came back to Poloniex after a couple of years of not logging in there not only did I find a substantial balance sitting there waiting for me, but also that a couple of the "shitcoins" that I had bought just for fun were now worth a lot of money!
I don't think either Poloniex or Bittrex is going to take your coins and run away with them, so it's really down to your personal preferences. Mine is generally Poloniex.