Just a hair bit behind, but I'll comment anyway:
I flew from Salt Lake City, Utah to Philly, PA to play up in New Milford, PA with some friends. I bought a hard-sided, lockable case for my 2 markers that would be making the trip with me. I stuck them in my checked bag (JT Paintball bag) and went to check in. I got there, opened my bag, then unlocked the gun case (first time I'd ever flown after all the new 'rules'). First question outta the guy's mouth:
"Where are your tanks???"
"At home on the shelf boss. You're more than welcome to check the rest of the bag just to be sure."
Sure enough he did (got a surprise with my undies though... no lace
), and he smiled and did what I dread: "Ruffle" my hair. Anyway, he made the comment that it was nice of me to leave them behind as it was a pain in the butt to get them taken apart to be able to fly, and asked what I planned to use.
"Buddy of mine's bringing a spare tank down from Mass. for me. Couple of them are driving down together, so they're bringing spare equipment."
The long and short:
Markers can fly, tanks cannot (commercial air liners). If you have friends that are driving in to play, have them bring spares. If not, rent from the field. It just saves you the hassle in the long run.