RE: Sig Tri Star Build
That plane was designed around the Cox TD 09 and if equipped with that motor will balance perfectly. I used it and didn't use a throttle but could have used a Medallion 09 if I had wanted to. It was a blast and of course I saved the wt of a servo, which today really doesn't mean too much.
Oh and why a TD 09 simply put is that it puts out the power of most sport 15's ,bar none the best motor that Cox ever made and almost completely ignored by everyone.
Dennis