The UI is clean (blue and white) and i can easily send and receive bitcoins.
When their website gets offline i have no access to my bitcoins, so basically they own my bitcoins, not much safe.
What that's mean about "easy to manipulate"?
Basically coinbase is exchanger.
may be he use 1 bitcoin adddress only 1time, or maybe he want to mixing his bitcoin
send btc to coinbase, sell it with usd and buy back after it your bitcoin get mixing
but i think xapo is better to do it
Nowadays there are many bitcoin mixer, and the number is just growing, that could work too,
Both coinbase and xapo does not give you private key but their service is good.
But if you want to mix then buying alt coins and selling to other exchange should work too.
i am not 100% sure but as far as i know you have to give your personal information to wallet service providers like coinbase and xapo.
so as a result the mixing part is useless, because the purpose of using mixers is staying anonymous which you won't have when using xapo or coinbase.
I use coinbase just to send or receive bitcoins, mostly just the "Wallet"
But i don't use it as an exchange because yeah it requires tons of documents to "verify" yourself.
And if you do then there is no anonymous trading and the bitcoin mixer is useless