I haven't seen them advertise custom matches or sponsorships on their website.
The benefits of membership are:
- viewing/downloading photosets for free
- 1 point ($2) discount on new matches
- 3-4 point discount on the match of the month (a random match from several years ago)
- viewing a 1 minute preview video of every match\
So I'd say a membership is worth it if one of the following applies:
- you're only interested in the photosets, but not the videos
- you're going to be purchasing all (or at least almost all) of the new videos as they come out
- the subscription price is worth it for you to see the preview videos to decide which you might want to purchase.
If you're only going to be buying a few videos here and there, I'd say you're probably better off doing it without a subscription.