I'm getting a kick out of this. The DLE 30 is a good engine, no debate. It CAN be better. But to say it is better because of a manufacturer noted HP rating is ludricous. 3w HAS and USES a dyno, as do others that make heavy use of the engine. The 2.75 HP number for the 28i is not a lie, but accurately represented. No graph extrapolation, no sleight of hand, no fudge factors, but obtained from real dyno tests many, many times. How one gains a full HP with the addition of 2cc's, poor tolerance control, lousy assembly oversight, a crappy induction path, and inferior porting is beyond my comprehension. Over a quarter million flight hours in unmanned platforms seriously attest to the reliability of the 28i, as well as change times in excess of 400 hours with the engine still providing peak performance numbers. Still in good enough shape that even after 400-600 hours they are still useful for a few more safe and effective years of model flying.

As Steve noted, it's useful torque that matters, and that torque must be obtained in an rpm band that would most effectively transfer to the propeller. Start breaking down power values in watts/litre and you start doing a little better power comparisons using a known constant for reference purposes.

The only areas where the 3w-28 lags behind the DLE 30 is in weight and cost. The weight is quite useful in many applications where better heat management is required. Heavy aircraft where more of the engine's flat rated output is required is a perfect example. The three point debate is moot since many, many airframes make effective use of the triple foot without any issues whatsoever, and they work harder than any model ever will. Cost is relative. Don't know how long the 30 will last yet but I KNOW how long the 28 will, and they do so repeatedly.

Yes, I have a DLE 30, have flown a plane with a DLE 30, own a couple of 28i's and have put a lot of hours on them personally. Over 2 thousand documented in the air and another 1,000 plus on the ground, and have access to many more in various induction and fuel configurations at any given moment. I'm not making any claims that a DLE is inferior or not a suitable purchase, but I am casting a lot of doubt about ol seabea's engine assessment qualifications. Which engine will safely pull the heaviest plane without cooking off? The 28 routinely handles well over 40 pounds using a deliberately restricted exhaust system.

I like the DLE 30 quite a lot but I'm not going to buy into manufacturer advertising unless I know how the data was obtained. If it came from a thust calculator it is seriously suspect.

Oh, yea, my oldest daughter manages to roll one of the family quads on a regular basis. Kid drives like a cop...