Mig,
If you can keep your balance respectable, I would go with the 120.
The H9 t-craft hits the scales at around 15 pounds. I have a g23 glow on mine......You have a simiular aircraft but lighter.
You can always throttle back. If your weight management is in the range of not having to put a boat anchor on the tail...I would go with the 120. I would even think about placing a larger fuel tank forward to manage the cg and weight .
The biggest dissapointment I have had with a plane is underpowered.
Good Luck,
DOC