Coinbase when buying with FIAT, despite their annoying commissions, just because of convenience. When buying them with cryptos, usually I use Shapeshift due to Jaxx having it built-in.
I have heard excellent things about Kraken off some friends though, been considering moving to that for buying/selling, however given how much of a total chore it is to set up an account on an exchange with ID verification and all that malarkey I might just stick with Coinbase...
RE: Where Do you Buy YOUR Bitcoins???-.- Community Open Questions Program