I have a number of AvioMac twins (70cc, 85cc and 125cc) since the Tower Hobbies days of importing them. The 70 and 85 now have some time on them and they are indeed smooth, reliable engines. They are weighter than comparable engines but in some instances not by much. Power wise they will turn props that many designer engines will choke on.

3D flyers need to look elsewhere but for IMAC pattern, scale and all around sport flying these engines provide great power, trouble free operation. Zenoah is considered tops in user friendly, reliable engines. AvioMac's fit into the same category.

Bisson makes great fitting mufflers but you need to special order them. They still have the patterns and will make what is needed.

Glad to see availability of these engines again.