I always trusted (as far as you can trust people you don`t know with your money...) Kraken because it was around in the beginning and never got hacked or went away.
In the beginning of the crypto world i have seen many exchanges going down or got hacked or just simply stole the money.
So it has a plus in my book even after the last 2 months the server was hard to reach.
But i can tell you that a long down time like this does not make me happy.

Like always...spread your investments!
So you spread the risk!

Latest news from kraken:
" Update - We are preparing to relaunch the site shortly. All orders have been canceled. More details to come soon.
Jan 13, 09:32 UTC"