its pretty easy to build the wheel of your dreams,
Honestly the nexus 7 is my favorite (also happen to have plenty of them used!)
why not buy the model bike you want with a single/footbrake and buy a nexus and have it laced up?
my opinion with internal hubs and folding bikes
internal hubs and drum brake front hubs are perfect for folders,
if your folder is badly handled,dropped,kicked, the standard deraileurs and hand brakes can and will be knocked out of adjustment.
not all 3 speeds are created equal for folders.
Sturmey archer,Sram have the gear changing bits on the outside of the nut-perfect to get wacked about.
the sram has this plastic piece that breaks when the bike falls over
the nexus 7 and 8 is rotated around the hub inside the stays and protected.
the nexus 3 has a metal housing attached outside the nut-its better then the Sturmey.and can take a wack.
as for the front on a folder drum brakes make so much sense, I have had an aluminum wheel bent in luggage making the hand brake useless,
my folder has drum, which works regardless.
again -this is my opinion with my folders.
mike in finland