I’ve been running an Alfine on a 456 for the last 6 months or so – intended to use it as a winter bike, off road and so far has been great. Don’t bother washing the bike, oil the chain a bit every now and again – that’s it.
Downside, it’s heavy hub – so whilst all the weight savings add up to the same most of the weight is centred on the hub. Weird to get used to but ok now I have. I Can’t flick the bike much, it’s not good on bunny hops, downhill it’s fine. There’s a big gap between the gears.
Plus side – I’m saving the price of a chain, cassette, jockey wheels, rear mech being ripped off, chain rings replacing – all of which I did the previous year, sometimes more than once at great cost!!!!