Propane versus gas?

I've been thinking about picking up a Luger since they're on sale, and getting a propane adapter. I was wondering if anyone on here had a propane adapter and if they could give me some likes/dislikes about them?

Propane stinks... but it seems to work fine.... i've had some minor issues with the valves.... but i think thats just cuz they're old on my mags.... Not sayin propane is bad... but i think it really depends on the gun... my gas shotgun for example takes propane a lot better than green gas or at least just as good, but i like how my blowback pistol performs on greengas better... propane does up the FPS slightly too... just fyi...
also the adapters work great

main good thing bout propane: cheap as dirt, FPS increase, seems to work fine
main bad thing: smells bad, might not work as well with blowbacks? (could just be my pistol, but idk)
....hope that helps