When I was shopping for my '05 LGT, I test drove a few various Legacy sedans and wagons and a few of them did have the shimmy issue. I consciously chose to purchase one that did not have any vibration back in Jan of 2005.
I actually think that the fuel economy is really good for the '10 LGT considering its size, AWD and performance. And in comparison to my current V8 (a hair under 20mpg avg, 90% highway, easy driving) it will be a very nice improvement. Hoping for around 28mpg when staying off boost.
I would be planning on installing aftermarket HIDs (maybe lenses too). Tap turn is a great feature that can be easily installed, and I really liked it in my '05.
The styling is actually one of the reasons why I am considering the car. I like it a lot and feel that it is rather muscular with the bulging fenders. The 18" wheels look really nice too. And I need the room in the back seat and trunk for work, so the size will be perfect. The M45 weighs a little over 4000 lbs... I am actually excited to get into a car that is around 3500 lbs. And the 6 spd manual is going to be a welcome change!
How does the car feel without the rear LSD? Is it relying on the ESP/TC to control wheel spin? How does it perform in the wet/snow/ice under acceleration? Is it still pretty easy to rotate it with the throttle? I used to love that in the '05 LGT.