I just bought a 2005 LT after two years with a GL1800. The GL is a better two up bike for trailering, the LT is better with one, and more fun to ride.
LT is better at braking (servo assist) and handling, weighs about 80 lbs less, feels like 200 less. Both a fine products leaning in slightly different directions, fit and finish on the LT are better, the GL is more serviceable, oil changes are not a stupid as with an LT. Honda's have more dealers. The electric windscreen is pretty slick on the LT, the GL windshield adjustment is crap, right out of WWII Russia, apologises to our Russian friends. Both have good ABS is you get comparable models, all Canadian models are ABS.
If you check the service intervals on the LT there are some scarey items that need early replacement like the timing chain guides, and valve clearance checks every 20k kms (valve check) versus 60k kms on the Wing. GL1800 are cheaper to run and maintain.... then there is the Honda frame problem, Honda covers the repairs, but you always think about this aluminum frame that was rewelded, the load yu are carrying and the beffy motor.
GL1800 runs fine on regular fuel, 2005 LT is hopelessly addicted to high test due to it's 11.5 to 1 compression... an issue at times when travelling in the boonies.
Which is better, I'm still not sure, but have spent my money and made my choice. no regrets, but at times disappointed at the $185 service intervals for virtually no real work, I fear the timing chain job... looks like open heart surgery in the manual.
Oh yes.... the LT has no gear whine!! The GL1800 sounds like an air raid siren at highway sppeds from the gearbox noise, they claim the square cut gears are stronger... my LandRover Diso had square cut gears in the diffs and they were quieter.
CB radios, forget going to BMW to solve it for the LT, it's your very own science project to source and build, the factory solution in Canada is $4,500 versus $1,500 for the GL1800. I added a J&M radio, it does the job and is definitely the worst performing radio for the dollar I have ever had... and I operate a lot of radios, have to run it full squelch, I suspect terrible alternator whine and fuel pump whine suceptibility.. haven't fixed it yet. The GL1800 was somewhat better.