Vince, by the time I'm ready to make a frame, you will be ready for the upgrade! If you can get a BF frame, well heck, that is the point of this thread.
Keep us posted on price, and sizes. I need a 56/60, so basically a 60 in their stuff, however they size them. Maybe there is a frame there you can't use, but one of us could.
I'm not particularly interested in a Brompton, though I was at one time, and probably could be again. I have the parts for a 406 build, which is the reason I am after a BF, or maybe a home made one.