I have Rohloff on an expedition touring bike. It's a superb bit of equipment, absolutely bulletproof as far as I can see, zero maintenance apart from an oil change every 5000 km or so - takes 10 minutes - and 14 gears, evenly spaced with 13% increments between them to provide a big range. The weight penalty is insignificant in the context in which I'm using it, and isn't that huge anyway when you net off the couple of chainrings and 10-speed cassette that it replaces. Plus your wallet will be a lot lighter, it's seriously expensive.

It has disadvantages, yes. As you say, it's a bit less convenient when repairing a puncture. More significant, for me, is that you can't just swap out the wheel (unless you have two Rohloffs, of course) so for example if I wanted to put slicks on the bike that would be a bit of a pain.

But the big question is, as you say, what have you to gain? In my case I bought it for a two-month tour on which I was going to be out of reach of bike shops for extended periods. I wanted virtual indestructibility. I'd use it on a year-round commuter for similar reasons. And no doubt it's an admirable piece of engineering, if that floats your boat. But for ordinary purposes I'd say it's advantages over a derailleur system come at too high a price. The Shimano alternatives are cheaper, of course, but from what I read they lack the Rohloff's legendary durability, and don't have the range.