I LOVE my actlabs guns. I'm not running mame .139 but I'm sure they work in them... I'm running a very slightly older mame than .139 and they work great.
I highly recommend the actlabs ones. I have a 27 inch tv in my cab and they work great. I prefer the look of them too. To me they had a Lethal Enforcers look to them, which reminded me of the arcade era I grew up in.
They work with snes9x (snes games), nestopia (nes games), Model 2 emulator, MAME, House of the dead 1-3, Virtua Cop 1 and 2, epsxe (playstation emulator), American Laser games (Mad Dog McCree and several other live action games), etc.
I love mine. I highly recommend getting guns on your cab. At the moment I seem to be playing those games more than anything else on my cab.
As said above, also I didn't want an infrared bar above my screen, especially considering my bezel around my monitor is tight to my monitor, so I went actlabs.