Three very different guitars. It makes me think you are wanting a Gibson just because you want "A Gibson." Instead of chasing a brand name you think you ought to own, I'd chase a tone you want. Which tone is it? SG Standard, Les Paul Standard, or semi-hollow?
The way I see it, the SG and the 333/335/345/355 are the most versatile of the three types you mentioned. Along with Teles, those two guitar designs make up the holy trifecta of world's most versatile guitar types (IMHO). The Les Paul does its "Les Paul Thing" the best of the lot, but it is less versatile over all, and IMO is at its best only when you can really open it up volume-wise. To me, a Les Paul is like a musical bludgeon. Brutal low-end thump that knocks you hard in the guts...but you really need to swing the hell out of a bludgeon for it to do what it does best! And you don't always have the room to do that in every band or for every song, especially if you are a sideman. With a LP, I have to put a lot of effort into playing to its strengths, and that can get old sometimes. I love LPs, but I would really dislike having one as my only guitar, or even as my only Gibson model.
