Originally Posted by
Robert Raburn
A key benefit of IGHs not mentioned: easy to attach a chainguard to protect slacks. My Nexus 8sp w/Alfine rapid-fire shifter has been nearly trouble-free for three years of daily commutes. The shifter gear indicator rattled, so I surgically removed it with a dremel tool. The chain-line makes for quiet operation. Another plus with the Nexus is performance--you can shift into larger gears under load (i.e., when sprinting away from a stop).
I wasn't going to say anything, until I got to that last sentence.
It's true that it makes it easier to find a bike with a chainguard. I have a chainring guard on my derailler commuter, but it wasn't easy to find.
A shifter that needs something removed with a dremel tool is not "trouble free".
My IGH bike has taken some work to get to stop being noisy, but the only part of that that's the IGH's fault is ironically the chain guard - the chain will slap against it when going over large bumps (like when going from the street onto the bike trail).
IGH's are traditionally worse than deraillers at shifting into large gears under load. A derailler has to be pretty messed up or bad to be worse than the IGH at shifting under load. Shimano IGH's - and probably some others - have gotten a lot better and you might not notice the difference nowadays, but they're not better than a derailler.
The IGH's advantage is usually being able to shift when it's not under load at all, like when stopped at a stoplight, something that you can't really do with a derailler.