I've had to slow down my P-60 and later P60SE in hot and high situations. If you suspect the acceleration may be an issue, after start do a medium acceleration to full thrust, stabilize, then chop the throttle. Let it run for a few seconds at stabilized idle, then do a slam full throttle acceleration. If you are going to have trouble usually the quick slam acceleration after you have already allowed the engine to run through the full RPM range will show the flame out or compressor stall. In my particular Jetcats I've noticed trouble with acceleration flameouts are usually not a forward blowing flame from a traditional compressor stall but a big flame belch going aft from the tail pipe followed by the roll back flameout. It can be quite spectacular when you don't expect it, the first time. I didn't come up with this test routine, rather I had Bob Wilcox on the phone one day and I talked him through what I saw once and he had me run through a few tests and then we decided to slow the spool up and spool down onramp speed changes. Ran like a champ afterward. I have to say I was at 5000 feet and the density altitude that day was about 8500 feet. My Wren behaves exactly like the Jetcat, same solution. At sea level I'd be surprised if this would ever occur.