I think it only gets so clean or clear, so to me it comes down to how quickly I can get that done. Raising the temp to close out fermentation, crashing cold (32-33°) and using gelatin at kegging, and keeping it really cold through the first week it's in the keg. I do use a very flocculant yeast strain, so I'm sure that helps. And I ferment in a conical FWIW.
These are low to average strength ales I'm talking about, but yeah, two days in the keg and I'm thoroughly enjoying it - one week in the keg it's done. That usually falls on day 14-17 for me.
The improvement in carbonation (as Martin pointed out) is the only real difference to me once I get the beer crystal clear, but after about a week that seems fine too.
There's been a lot of talk here recently about Marshall's blog, and I think this is pretty close to how he's doing it. His ale schedule is around 9 days I think.