My current airline allows us F/Os to taxi the aircraft, so we effectively swap roles of PF and PNF for each sector. Previously, in my previous airline, there was no tiller on the F/O side, and the captain would normally take control once the aircraft was slowing down after landing. There was no specific time/speed to hand over. But we always started/shut down the engines. Some operators don't even let their F/Os do that. I don't really understand why not.
To be honest with you, it took me about 2 taxi experiences to get the hang of it. It's no big deal at all. I still get the odd input from the captains on techniques and speeds, but its always welcome.
