I can't speak for others, but MANcheck doesn't have a problem with this kind of thing. As basschick said though, just keep your MANcheck's and Sexkeys separate from one another. If you want to link all of your MANcheck sites together in a sort of hub, that's cool, just don't create any leaks to your Sexkey sites. You'll earn an extra buck per sale and $2 on rebills if you site is exclusive.

Never, never, never put more than one AVS entry script on a gallery. You're just depleting sales. If you had a MANcheck and Sexkey script on the same gallery, why would I buy a Sexkey, I'd just use my MANcheck. Sounds basic, but you'd be amazed at how many webmasters don't get that one.

If there's anything I can help you with as far as MANcheck is concerned, just let me know ... michael at mancheck dot com.

Cheers
Dzinerbear