I've ordered some Apogee F10-4 motors for this rascal. Comparing the F10 thrust profile to that of the F15, I find that the F10 actually stays above 15 N longer than the F15, and follows that up with a heck of a long burn, remaining around 9 N for the remainder, which is enough to keep it pointing up for the remainder. The impulse being 74.3 N-s, I'm going to slap a B6-0 on the side for some extra oomph on takeoff.
This sets the stage of course for my next hat trick which is that as soon as that flight is over, I'm going to load back up and put a C6-0 in that side pod to push it into G class and go after that record while I'm at it. Given the long burn and lower percentage of total time before deploy spent nose down waiting for the ejection charge, I'd be willing to bet it does close to 3 minutes in both configurations. More if there's any lift. And if it's windy, well, we're not flying, even though I've launched this thing in 15 mph winds without it weathercocking on the F15.
Looking at the numbers, the F10 by itself actually gives more right off the pad than the F15, and the F15 has demonstrated the ability to safely launch in fairly strong wind gusts. If I could allocate the funds for an 18/20 reload casing I'd get one and run C2.3 reloads just to give some extra cruise thrust. The F10 has a nearly 8 second burn and my main concern is not letting the model slow down too much after that initial burst in the first 2 seconds.