I did a TCT one year, this was before I started documenting stuff. It was great, the kids loved it, BUT, after that year I stopped using it. Compressed air is a pain in the butt because I've got to find somewhere to put the air compressor, and it's loud when it refills.
I haven't ever tried with a self-contained canister though... I've heard that some people have had success with that, but my guess is I would run out of air before the night was over.
Not using air makes it hard to do some of my props though. I mentioned before that I want my guy in the casket to pop out.... I bought one of those 2 foot tall "graveyard ghoul" popups from k-mart a few years back to use as the mechanism, but it didn't pan out... the device, even with a dedicated power supply, can't handle much weight. I'm going to try to beef it up next summer by maybe adding bungee cords or a stronger motor.
I really want to do an axworthy ghost too. I've tried several times over the years, experimenting with different types of line and pulleys, ect, but the line always falls on me. It's one of those deals where if I have to get on a ladder and fiddle with it every day it isn't worth doing.