I was sceptical myself before I went to WIM as to how much difference it would make. I was pretty new to my car, and really doubted that it would make that much difference. ok, I was happy that it would sort out premature tyre wear issues, but that was pretty much all I was expecting.
Wow, was I wrong or what ! It was nearly a year ago now, but I can very clearly remember the trip home from WIM on the motorway. It felt like a completely different car ! Much, much more stable on the motorway, and when off the motorway the steering was a lot better, the car handled so much better.
I guess in a way it shouldn't be suprising, after all the wheels/tyres are the only thing putting you in contact with the road, and if you change the way those tyres are located on the road (i.e. via the suspension geometry), then it makes sense it can change things a lot.
Never mind the tyre wear issue (which is important enough on its own), a trip to WIM (if it hasn't been done already, of course !) will totally transform your car, and increase your driving enjoyment no end !