I picked up the Brownie Reflex 20 for about $12 at a local antique mall back in July. I have a thing for Brownies, and for pseudo-TLRs, especially ones that have a zone focus rather than fixed.
I respooled some expired 120 film onto a 620 spool — my current method is to sit on my basement steps in the dark to do my respooling, and I really hope I get faster at it with practice. Unlike the first time I tried respooling film, I didn’t create any light leaks this time. In fact, the camera was pretty solid in that respect, too.
The short version: It works. It’s not my favorite, but it takes decent photos, and the camera itself looks kind of cool. The shutter speed is so slow that handholding is sometimes iffy, especially with the focus set to infinity. It did take some decent photos in bright sunshine on expired ISO 160, but there’s not much character to them, in my opinion — not much to distinguish this camera from other box cameras I own.
I probably won’t be taking this one out again, but it was a cheap and kitschy addition to my Brownie collection.
When I first bought this camera from the antique mall some eight years ago, I didn’t own any other 620 cameras — and even if I’d had an extra couple of 620 spools handy, it hadn’t even occurred to me to try respooling 120 film onto a 620 spool. I managed to run two rolls of 35mm through the camera to try some 
I picked up the Pickwik Reflex at a garage sale for $4. As I recall, the woman assumed a camera that old (circa 1940) would only be good for decoration; she was surprised when I told her it looked like it would actually work.
I picked up the Brownie Bullseye at a garage sale at the Old West End Festival a couple of years back for $3 or $4, boxed, with the flash attachment. After letting it sit in its box on top of my camera display shelf for a year or two, I finally got around to running a test roll through it this past May.