I had a nice 6" 45 Bullseye gun that I thought about replace with a new build but then I think 10mm might be kind of cool too. I would more than likely use it more for accuracy shooting. But that's just me. However a 10mm pig slayer has some appeal
I would go with a caliber that I already reload for, but although they look cool, I think that 6" 1911's have little practical use, even in formal target shooting events. For that reason, I'd never consider one.