There's a website that needs more constant updating. Sold out of the GLA lamps well over a year ago. In any case, it's no doubt available thru both sources - though not well advertised on either.
One wallet size or slightly larger controller is no doubt much like the rest in many ways. It's more in the details and price in it perhaps more than anything else I assume. I use what I'm used to, and have limited experience with other controllers other than the Litl' DMXter which is also useful, but I forgot who makes it.
Features I would look for would be in size, Transmit and auto fade mode for all, some or one channel; Display DMX in Decimal, Hex or Percentage; Updatable and customizable fixture test menu, long battery life with auto off option, and scenes of memory that can either be programmed or imputted. Above this, I would trade the fixture test for timed fades and more realistic scenes. Above this, and what's often useful is a cable test mode.
Other sources might be:
Artistic Design Licence (Controller Mfr.)
http://www.artisticlicence.com/ Infinity Visions (Controller Mfgr.)
http://www.infinityvisions.com/ ELC Lighting (DMX Tool Mfr..)
http://www.elclighting.com/