I use Kraken, does not have a nice UI, but I find it to be a very reliable and good exchange with many options (at least it features all the things I want to buy, EOS, XRP, and XLM). Of course, it also features BTC and ETH as well as their cash variants.
I have also heard some good things about coinhub (a friend of mine uses it and finds it very good). To be honest, I also have an account there, but rarely use it.
Last week, I wanted to check one of the Japanese Exchanges listed by @dollarvigilante but I did not have the time to check them out yet. I hear Bitcoin is big in Japan, therefore I thought they may have some advantages over other exchanges because they (may) offer more services because Bitcoin is used more in Japan.
RE: 2 Cool Websites To Check or Predict Your BTC Investment Income!