I've have a 46 UCD powered with a Saito 100 for over a year now. The Saito 82 is plenty of power but after watching one fly with a 100 I had to have one and never looked back. You'll have unlimited vertical and you can never get behind the power curve no matter what attitude, altitude or speed. I fly with a APC 15 x 4" prop. In reality you only use all the power is to show off vertical climbs. The plane is made for slow flight so I have to be careful with the throttle. This is my 2nd Saito 100 and they are a great engine. it has a 3 year warantee and they stand behind it. No questions asked.
K.O.