I can endorse coinsmarkets.com - I've been using it for a few months without any issues.

They are often the first exchange to add a new coin or to update when a new wallet or blockchain comes out.

They have responded promptly to every email.

Not every staking coin works (pays stakes) on coinsmarkets, for instance they have COLX but it doesn't stake there. They told me that this is because some wallets are more difficult to integrate with their scripted accounting systems for payouts on stakes.

There *are* some scam coins on the site, but they seem to care about quality. For instance they described one altcoin to me in email as being "just like all the other coins this dev makes, since nothing new here we don't want to add it."

Coins stake well because your network weight is combined with all the other coins on the exchange.

There are some funny trolls.

Their accounting system credits users for each stake reward instead of adding it all up into a single daily payment.

Overall experience B+/A-