welcome to RCU Lee, glad to see you've joined.
Radyfly,
I use a 16oz tank with my focus/webra. can get one complete masters flight and some additional practice manuvers before landing. 2 complete sequences would be pushing it. there is no reason I used the 16oz other than thats what I had laying around at the time

I run 15% cool power and have since the engine was new. the plane has well over three hundred flights now.
Vofly,
I have a TT 1.20 pro at home as well. I started the same as you lokking for a plane for it, but ended up with the Webra / bolly 590 muffler. you would not be dissapointed with that combination. do you already have the header/ pipe combo for it? I had trouble finding a header for mine this spring.
Hubb