Netvault vs Appassure/Rapid recovery?

Anyone know the major differences from Netvault and Rapid recovery? Both seem tusps tracking o do nearly the same, but I believe netvault may be more for entespeed test rprise, with support for many many more machines and different OS? Or are there other things? We currently have appassure, pretty happy with it. But Dell called and was talking to upper management anshowbox d mentioned netvault, so now we have conference call next week.