I went from the VTX to the Goldwing too. It can be too cramped for bigger riders. Taller riders tell me that their knees feel too tight next to the fairing.
No idea what GL stands for, and I own one. Go figure. Most people just say the GL1800 is the "model" identifier. Like, what does VTX stand for?
I would recommend you go to the dealership and sit on one, no kidding, for like an hour. They take a little getting used to. They are a little sporty, in seating position, and powerband and they are wicked comfy rides compared to a VTX.
At first it'll feel like a battleship and then it starts to get smaller feeling as you get used to it. Mine has more "touring" tools on board than you can really use/imagine coming from a VTX.
The first time I turned on the heating system and tooled to work I thought I was in some kind of twilight zone movie. Its amazing.
I do miss the rider space of the VTX and the heel shifter, but we all adapt for what we like/want.
Many dealers allow you to test drive a Goldwing. Just don't be too surprised if it feels like too much bike at first. Again, they feel smaller with only a week or two of practice on it.
I can't think of any big negatives, except the price. The good news is that they are worth the money, in my opinion. The other minor point is that it takes a little time to learn to ride (compared to the VTX) and the seating position isn't as comfortable as you might imagine. Cruisers are really comfy for limited timeframes and touring bikes are designed for long term sitting (but that doesn't necessarily equate to comfy).
The big benefit for me was the wind protection. Its superb. It has a lot of cool stuff, potentially. I like the sound system (even though I had one on my VTX as well). The heating system, cruise control, and the integrated GPS are nice too. Overall, I like the weight, stability, confidence on the highway, and the overall power also.
I kept both bikes.