Raise seems to have quite a few negative reviews, so be cautious. I tested it out with a $25 PSN card (that totaled $16.66 at checkout) and everything seemed to work smoothly. Instead of waiting for the code in an email I went to my account on the site and found the code ready to use within 5 minutes. So I added the funds to my PSN immediately just to be safe.
I have a referral link if anyone else wants to try.
Raise is ok until you experience a problem. I took advantage of the Groupon deal a couple weeks back for $30 of Raise credit for $15. I used it to buy a couple Xbox gift cards. One of the gift cards worked fine ($10), but the other came back invalid ($25). I contacted their support about it, received an email the next day telling me I needed to submit a screenshot of the problem I was having. The only issue with this is once you submit a support ticket, it locks the purchase so you can't view the gift card anymore.
Thankfully, I still had the Xbox app open on my PC with the code typed in, so I was able to screencap it. I sent in the email and attached jpg, and I never heard back. Their support ticket said the issue would be resolved in a week, and when that week passed, I tried calling them. The automated system told me I was first in the queue and that an agent would answer my call soon. I sat on hold until a second automated message told me that they were experiencing "high call volumes" and all agents were busy. This cycle repeated for 15 minutes.
Finally, I hung up and decided to contact Groupon directly. I was worried they'd tell me "Hey, the code we sent you worked fine. Your issue is with Raise." But after attempting to call Raise themselves and getting the same outcome (ie. nobody answered), they issued me another code. So, I rolled the dice again with the new $30 of Raise credit, and thankfully this time both gift cards worked. So, yeah...if your codes work, you can get good deals. If not, use a form of payment that you can report the charges as fraudulent if things go south. I felt very fortunate that Groupon was decent about the whole thing.