Hi, Gil - I still have the prototype and it has turned out to be a fine little sport engine with no negatives. I forwarded an acceptance to the manufacturer through Brodak, so, I assume that production has begun.
We originally specified that the engine run on 10% nitro but I tried 15 and 20% without any problems. The prototype engine has a copper head shim which, I assume, makes it a bit more conservative, allowing more nitro.
I removed the shim and hopefully, I will fly it this weekend to see how the performance is affected.
You should keep in mind that the engine is set up for beam mounts and requires a separate tank.
I suggest you contact Brodak by phone regarding the delivery schedule - he may not have updated the info to the website as yet.
Hope this helps.
Bob Z