Sturmey Archer has the best parts availability, pre-2000 were made in the UK and there is a massive parts supply available. The post 2000 are built in Taiwan, but parts seem to be readily available. I use vintage Sturmey-Archer AWC hubs with no problems. I have one bike with a Shimano Nexus 3 coaster on it, haven't had enough time with it yet to know how well it is going to stand up. I have one Sturmey Archer AW that is from around 1970 (non coaster) that has well over 35,000 miles on it.
Aaron