I have the OS 1.20 AX on an Excelleron. The two big advantages of the 2 stroke 1.20 is power and vibration. There is more power and less vibration with the two stroke.

The two aircraft are similar in size and weight so performance on the Excelleron probably equals what you will find on the Venus II. Using the 15-10 prop, I get very good performance. As someone else said, now that I have more than 5 tanks of fuel (recommended by OS in the manual), I can lean it out a tad and go to a different, more radical prop and get even more.. if I wanted to. It is adequate for my needs with the current configuration. I think it's a great choice (OS 1.20 AX two stroke). And a tad less in the financial department. It starts cleanly and warms up very quickly, and has remained very consistent.

DS.