I'm not going to be ordering the 46mm myself. I've got one of Joe McGloin's film slitters, and I can just cut down any existing 120 film if I want to feed my Yashica 44a. (Also have half a roll of 46mm Agfa Portrait XPS-160 in the freezer which wasn't too badly outdated when I froze it.)
Note that if you intend to do this yourself, or even recycle existing 120 backing paper for use with new 46mm stock, you need to spool the cut-down film backwards and count down from 16 to 1, or it won't line up in the red window: the 4x4 track on real 127 paper is on the opposite side of the strip from the 6x4.5 track on 120 paper.
At the moment, I'm trying to decide between the 90mm FP4+ and the 91.75mm HP5+. Can't afford both at the moment. I'm leaning toward the faster film, even if it is $30 more, because none of my 3A cameras go much below f/8. The exception is the (not-yet-working) Graflex 3A, but that one has a shutter that goes up to 1/1000, or did when it was new. I've always wondered what the heck they were thinking when they built that one, back in the '20s, when Super-XX was as fast a film as you could possibly get.
(On the other hand, I do have a 90mm reel, meant for industrial X-ray film apparently, and actual 122 doesn't fit it very well. Have to think about this some more.)