The service is great, it is legit!
One thing I should note - if you order during the night be sure to realize they process orders during business hours. So you'll have to wait - the system isn't instant automated.
You order it and during their business hours they'll email you and tell you to send your ZBrush Core serial to the proper place and then it's handled from there.
Overall a very smooth process and I'm happy with it.
Legit upgrade with all the fixins! Any little bit that you can save with this beauty is helpful. I greatly appreciate this opportunity. The files came very quickly as well so I was up and running the full version within about 30 minutes. Very impressed and would highly recommend. Great program and great place to buy it from! A+