Oh I know the VX has plenty of power, one of the reasons I bought one.
The kind of "knockoffs" that I see out there have engines that you typically see in passenger cars, not light Trucks and SUVs.
Take the Ford Escape, I believe it has a Taurus engine. The Rav-4 ... stands for 4-banger. While these engines aren't meant to give the kind of benefits we enjoy with the Vx, they are meant to be able to get great mileage and be able to pull the car up and down the highway at 80mph with two kids and a load of groceries in the back.
This is the inherent insecurity I have with my VX, that people will confuse it for a econo-ute like a Kia or something. I suppose I should put some kind of nasty sounding exhaust on it :P
Oh as for GM pushing Isuzu out of north america... its been documented on several places, but if you go to the isuzu 4x4wire forums and do a search, you can find out all you need.