I remember both the AVI products and the MPC products. We were dealers for both. I do think it possible there was only one or two runs of B3-5m motors (and B3-3m) reordering those always had a stock in condition, where some of the others had a waiting time once or twice. MPC was one of our more popular sellers.

We bought every size of AVI motor from 1/8A-F and the interesting thing to me was the build quality was very consistent and the sheer variety of sizes was amazing. So they were clearly targeting an aspect ratio in the design. Also many of them had the delay charge glued in in a smaller tube. That would be helpful for short run larger motors.

MPC, AVI, FSI and other BP motors of the time were often no better than about 90% reliability. Even Estes first generation motors like the D13 and E15 were similarly of modest reliability.

Seeing the stuff be saved from the dumpster makes me happy. The fact that didn't happen at Vern's house is sickening.

Jerry