Rizzy, I see no reason why you could not fly the Profi on your trike. Garrett is absolutely correct on his advice to get the electric trimmer. You would have the ability in flight to force the wing to fly slow at a higher AoA or adjust the speed upwards. If you are concerned about the rpms that would be required for S&L flight on the Profi you can simply use the electric trimmer to dial in the rpms where you want them. It might be that at the fastest setting it will push your HKS a bit but you have complete control on neutral flying speeds with the trimmer. It may well be that you can also get the desired speed range on the Mustang 15 too with the electric trimmer but my guess is the Profi being double surface will fly faster.
Rizzy, Cathy Montgomery indicated on TPS that she was pretty sure that Aeros was referring to 2500m not ft and that sound reasonable to me. Over in the Ukraine they think in meters not feet. 2500m is 8200ft. You do not expect to be doing much flying at 8200 do you?