Opinions are like certain body parts, everyone has one! Mine differs from Dano's.
I've owed four LT's. 01-52,000 miles, 03-51,000 miles and two 05's-71,000 combined miles. There are subtle differences between the 05 up and pre 05, but when added up, they are substantial, IMHO. The following are the changes on the 05 up. Three degrees less rake to the front end. Results in much more nimble feel in low speed manuevers. Progressive damping in the rear suspension. Noticeably better ride. Redesigned dash. On board computer a part of the dash layout now, closer to your field of vision while driving and reseting the various windows on the computer can now be done at the handlebar with a touch of the BC button. 16 more HP. Noticeable in the higher RPM range. Redesigned headlight. Much better than the previous design but could still be better. Trunk handle. Front turn signals also running lights. Cosmetic changes to the tupperware, BMW roundel, etc. I might have missed some. This is just a quick list. Any additional money would be more than worth it to me.......but then maybe it isn't to you! Your call.