The 2,8 12v is 174 BHP but rolls more like 185, the 2.9 12v is 190 but more like 195-200 and the OBDII is 174 but more like 190-195.
The 2.8 24v is 204BHP but with a remap, exhaust and filter it can be closer to 240, mine is 234BHP!!
The
problem with the 12v is that its not as responsive as the 24v and its a lot older. If you get a 12v its gonna be fairly high mileage, and if the chains havent been done then you could be forking out £500 straight away, there also isnt much room for improvement over stock, whereas the 24v has more room due to the VVT etc.
R32 is the best option, but try finding one!!!
Also, a lot of VR owners are now turboing their motors so a lot more second hand chargers are coming up for sale.
Oh yeah, dont forget to upgrade your brakes