XpoSled Prowler on Wheels
 

http://www.armoredfitness.com/

Reminds me of the Smith Machine of Prowlers.
I'd have to try one to see if I liked it.
Looks expensive though, so doubt that'll happen.

I would be worried about too many moving parts. The fact that it has a chain would make me a bit nervous about purchasing one.

kinda cool, but not sold yet.

Breaking the Prowler free and getting it moving is one of the biggest parts of the challenge. I'm guessing this new version won't have that.