Hi
I have fitted the Bilstein kit of four shocks on standard springs,with sport pack 2 (16 inch alloys and std springs),it does not affect the ride height that I have noticed.The set up is as recommended by Bilstein giving the most ground clearance.
It is still a very firm ride,but much more controlled,when you do hit a pot hole,you do still feel it,but are not launched towards the nearest hedge!
The wife will now travel in the car,where as before she said it was too uncomfortable !
The handling is great with these shocks,but to be honest I would prefer the ride to be a little softer.
You do have the option of the original MG soft ride kit as fitted to 2005 my onwards ,these are available from many sources including Rimmer's.This will also save you a couple of hundred pounds.
I keep looking for a used set of later soft rides springs, as I would like to try them with the Bilstein shocks as I think that it may be the perfect compromise. (anyone got a set for sale ? )
Hope this helps ,I know it is difficult choice,especially with the heavy costs involved.