Jackal, only the RS, Extreme, RS450 and RS2 (RSX in the UK) have got the quick rack. Only the Extreme has the uprated bushes. The Makinnen has inverted dampers, and shorter springs, but other than that is the same as the GSR.
On the exhaust front, they are much of a muchness. Make sure it is a 3 system all the way through. Get a decat pipe, and replace the downpipe too.
The Piper is pants compared to the other filters, and won't give you as good an induction noise as say, the Blitz or the top end HKS stuff, or as much flow.
With a decent exhaust and filter, expect around 15% more power, better throttle response and a slight torque increase.
If you skimp on the downpipe, decat and air filter you will get noise, but not much power.
The Magnex is quite loud, as is the Blitz exhaust. The HKS super drager is realatively quite. Power Engineering exhaust has a good sound, and I have heard that the Scott and amp; Hayward one sounds nice too. Apexi also do nice filters and exhausts too.
. As for teh induction kit, I dont see any reason for spending more than 80 quid on the pipercorss... the HKS one doesn't appeal.... maybe blitz if I dont get piperX. I reckon its all much of a muchness - I just want the thing to sounds a lot better and loosen the feel up a bit and most of whats available will do just that. Ive done a lot of searches on teh board and there is advice for all sorts of best combinations e.g. HKS dragger with Magnex downpipe etc... but I am happy to go with what ever - everyone just recomends what they have got personally. Mind you, some exhausts may be too quiet or too loud for some tastes and the blitz induction kit is advised against if you are driving off road as it lets stuff in. HKS mushroom syou have to replace every so often.
