tl;dr:
*There are two 2269 variants. The one with arrow keys in the shape of a plus has a decent case, the one with an "inverted T" arrow cluster has a very not-decent case.
*The SMK second generation white Cherry mount switches are phenomenal, but easy to bottom out on.
*The caps are nice, relatively thick doubleshot ABS.
The one on the left has FCC ID IFS80-2269-1. The one one the right has FCC ID BNX84H80-2269-1. From here on I'll refer to them as "T board" and "plus board". Besides the arrow keys and case, the two boards are identical. In fact, you could desolder the switches in the plus board's arrow cluster and resolder them in the inverted T position, and they would work, as long as you changed Home to "Up" in Autohotkey or something.
Top is plus, bottom is T. You want the plus board. The case weighs half a pound more than the T board's and is much higher-quality. My ten year old brother could probably snap the T board in half with ease. It's bad.
You can see my T board is broken. It was packaged well, and doesn't appear to have been abused in shipping, but the PCB broke anyway because the build quality is awful. The plus board has an equally flimsy, fragile PCB, by the way.
The switches are SMK second generation Cherry mount. These are from the same family as "Monterey" blues. The stems feel lubricated, and are much less frictiony than my Alps SKCM, especially on off-center presses. They feel a lot like MX blues and greens, but thocky instead of clicky. I attached a video just below. By stacking pennies, I measured between 65 and 85 g of force to actuate each switch, with an average of 70. The outliers are rare, and despite the wide range, they feel very consistent - I never would have guessed that my O key is so much heavier than the rest. This contrasts my genuine complicated white Alps board, where each switch seems to have aged different from the rest, and the inconsistencies feel very unpleasant (until you clean them/bend the stems back).
It's hard to avoid bottoming out on these because the "click" point is very near the bottom. Still, you can get used to them. SMK second gen is my favorite switch.
There's a diode symbol on the bottom of the switch assembly, but my standard glass package diodes are fat and the switch won't close back up with them in place. In the spot where the diode would lie, there's a wire that solders into the PCB, apparently for stability - but you could use it as a connection to jump over a PCB track, if you're using these for a custom design. Springs are the size of Alps springs. From top to bottom: SMK, Alps SKCM, Cherry MX blue.
I thought these couldn't be plate mounted, but as jacobolus pointed out, they
can 
The caps on the T board are quite loose, and can easily be pried off with fingers alone. The caps on the plus board are tighter and require a lot more force. This isn't due to the caps, but the switches. The switches on the T board have skinnier stems.
This isn't a big problem, I think. I thought this was causing cap unevenness on the board, visible in the above picture, but I later realized that the switches themselves are unevenly mounted to the PCBs.
From left to right: Focus 2001 (comparable to most modern stock caps, I think), Laser, and vintage Cherry Corp. The caps are of a decent thickness. I love the legends, can anyone guess the manufacturer? They weigh a little more than a gram each.
What else? My board hooked up through a passive AT-PS/2 converter, and then through a passive PS/2-USB converter without a hitch. The PCBs have diodes (about 40 IIRC) indicating they have some rollover capability.
I think the poor build quality of the case and PCB can be forgiven given the nice caps and excellent switches, if your PCB doesn't disintegrate in shipping like my first one did. I recommend the 2269.
