I tried it for the first time a couple of days ago.

I followed the instructions to send 0.4239 BTC to some address. Some time later I got a confirmation that the funds were received. The message said "You should now wait to receive a third email, which provides instructions from your carrier in order to credit your mobile phone. This email may take up to a few hours to receive."

I didn't receive the follow-up email or the credit on my phone after 24 hours. They've ignored a follow-up email as well as a message I sent from the contact form on their web site.

At best, they're disorganized and their customer support sucks. At worst, it's a scam.

I've already decided that I won't use them again. I'm interested in hearing if anyone else has successfully gotten credit.