Mark 1 handling can be improved by putting better shocks/dampers and moving away from the factory fitted Pilot Sports. Whether this will make it as well sorted as the Mark 2 is debatable - you can fit the Mark 2 rear subframe to the Mark 1 which apparently helps alot.
I dont know where Nology got their Mark 1 from but I would not describe the handling as standard as impeccable!
Mark 1s are only marginaly more powerful in real terms than Cups/172 and they, without modification, would not keep up with a Cup round a twisty track. Thing is, it is not just a numbers game - part of the fun of the Mark 1/2 is that it is an oversteering, RWD v6. It is a challenge to drive it properly quick but when you do get it right it is rewarding.
When I brought mine I test drove a Cup, CTR and Mini Cooper S and although this is probably inviting a flame war - IMHO: the Mini Cooper S was the best handling but was woefully underpowered, the CTR had 2nd class post between the steering wheel and the front wheels, Cup was good but nothing could compare to the first time you drive along the road with the noise of the v6 where the rear seats should be.