I'll try to answer the original question with " only a few select modelers / manufacturer's " have received the Mamba that I know of......"for further testing". In talking with " the testers" their experience thus far is that the engine seems to perform well. As of yet, I don't think you can place an order and expect delivery tomorrow for an engine.

Heard the " two week delivery thing " at Florida Jets and again at Superman. Even had a well known jet modeler stand with me witness the statement. I don't know.....credibility, price and having to lug around a scuba tank again will likely prevent me from looking any further. There is certainly a large market potential out there for a reasonably priced, well designed commercially produced Wren sized engine. I do know that Simjet and PST are serious about accommodating this market.

SWB ????