Thanks firecolon. (Also, thanks for choosing the name 'firecolon'...)
To clarify, I'd have tuition+stipend at either school. The A stipend is average, and the B stipend is quite nice, but the cost of living is also higher at B. And in any case I've been working for a couple of years, so I have a hard time getting excited about any of these stipend levels. For funding I'd call it a wash.
The size difference is also a wash, that's not particularly important either way.
The #20-ish is out of a large number of programs, I'm in a pretty big field.
I think I'd have a clearer choice for B if it weren't *so* urban. We're talking smack in the middle of a humongous city. High-rises, subways, honking taxis, the whole deal. (I won't give the school name, but I'll let you extrapolate.) It's not somewhere I would voluntarily move to unless there was a major reason driving it. But of course now there might be...
Hence the deadlock.