Only took the better part of 5 years, but I was finally able to track down the Quest X-15 MMX set. This one had a damaged fin, but it was a clean break and a little CA made it just like new. Today was cold and overcast, but windless. I decided to hike over to the park and see how she flies.
The X-15 uses the cord mounted shock cord, so I stuffed a small bit of wadding in there hoping that nothing would be scorched at ejection. Loaded up an old-style ignitor on the Quest Micro pad, pushed the button, and off it went. It flew fairly stable to about the same height as the LPB Blackbird. The streamer deployed successfully and it landed about 4 inches from the pad, unharmed.
Also flown was my LBP Little Joe II and the new Quest Boingo. Both had straight flights. After flying the LPBs the Boingo really got up there. For some reason mine likes to whistle on the way down. Kinda fun in that "Heads Up" way
Too bad this model is so hard to find. The flat black plastic really makes the decals pop, and it seems to be one of the better performing LPBs.