My YS110 gets about 20 minutes on a 16oz tank since I really only fly around half throttle most of the time with the occasional full throttle vertical climbout from a hover or going vertical for a stall turn or Knife Edge loop

I have flown the:

CG Ultimate
DP Ultimate
Aeroworks Ultimate
SIG Hog Bipe
Sundancer

Of cource my favorite is the CG Ultimate, with the Sundancer second and then the SIG Hog Bipe. The DP Ultimate was nice as well as the Areoworks Ultimate but I did not feel they were as good as the CG Ultimate.

With the CG you have the option of doing either the single elevator servo in the fuselage or the dual servos as I did. Smoke on any of them is mostly determined by the engine. Gas definitely produces better smoke as they run hotter but the YS110 should do well. I just need the smoke muffler and I could do it.

The CG Ultimate cannot go gas as I have not found a gas engine as light as the YS110. The only thing close is the RCS 1.40 but it is almost 10oz heavier than the YS110. The SIG hog bipe will not be able to gas at all and the Aeroworks and DP ones can go gas if you use the RCS 1.40

As far as room for the smoke system, they all have plenty of room.