I ordered a couple products from them, not sure at the time they were legit of course, but the prices were good. And they had a wide variety of products I was interested in.
When I needed to contact them about the download they were available to me right away. I asked why the software was so cheap and they said something about volume dealers. Satisfied me. Result: I have had no problems with the software I bought.
I had no problem reaching them and getting information within 24-48 hours.
There was no way to know if they had legitimate products except to verify and register with Microsoft and that all went as expected. No viruses or other problems.