while you wait...
here's my M60B in .357. i got it from krale and it came with out the fill port on the gauge, so i also had to order one from wes. where i also got a spare magazine. i also had an annoying waiting time, since out of the box the gun came with a defect fill adapter and krale had to send a new one. the first thing that happened was that the o ring of the the bottle broke, when i first detached it, the vendor also send a few new ones, but so far it did not happen again. still i wanted to have the fill port on the gun. i also added an alsafe CF bottle which might be a tiny bit too long, as it touches the moderator (which i think works well, compared to shooting without) with a little bit of tension, to my understanding i would rather not have a connection there. hopefully i can find a some kind of extension to add clearance. another aspect of the new fill port is that the original foster coupling from snowpeak has a crappy plastic valve inside, which for me audibly leaked all air directly after the first filling. (wes said, if that happens, the valve can be reset by pushing a pin into it, but i do not like the idea). knowingly, he also included a better foster coupling in the set, with a brass valve inside, which works, but it's profile is too long, so if that is attached the bottle can't be unscrewed, without taking off the barrel shroud or the foster nipple.
anyway, i like the gun, but it was also my first and i have had no clue, if i knew better, i would have taken one in .30 as well. now i hope the external plenum (as seen on youtube and briefly also here) will be available in regions, the shipping does not cost many times the actual items value.