They haven't let me down yet
I've only used xboxlivegold twice, to buy memberships as gifts. Both times, the price was great (compared to other sites I've checked) and the code was delivered quickly. *Really* quickly. Also, both times the codes worked flawlessly. I've read a few reviews where folks said their codes didn't work, but I haven't run into that problem. The next time it's time to renew my membership, I'm coming back here.