ehmmm.. I been using them on my website but got this letter a few weeks ago :

It is with a heavy heart that we have to announce the closure of CoinPayments.net. FinCEN has ruled that Bitcoin is in their purview which would make us a money transmitter. We simply do not have the resources to register with FinCEN and most of the 50 states as a MSB and comply with all of the AML/KYC laws (and no realistic way to raise the funds to do so.)

The shutdown will happen in 3 stages:
1. We will stop accepting new user registrations effective immediately.
2. We will stop processing new transactions at 11:59:59 PM EST on March 24, 2014 (transactions already in progress at that time will be completed).
3. The website will otherwise remain operational until 11:59:59 PM EST on March 31st, 2014 when it will be shut down.