Hi P-Diddy.
The guarantee given for airplane manufctures is, in my opinion, a funny thing.
First, they, on theory, will only cover if you use the recomended engines. But everybody can say that a Showtime can't hover with the manual's engines.
To do what this planes are designed for, you always have to over-power it and, so, you will never get any cover.
I saw some guys in some threads saying that H9 will not cover their planes (a Showtime or a Funtana X 100, I don't remmeber well), because they used a O.S. 120 AX.
I have an O.S. 120 AX. This engine is not that powerfull. I had mine in a Funtana 100 X and the pull out power was very poor. Now I have this engine in an U-Can-Do 60 size and I don't have a goot amout of power to pull out too. Showtime is a more heavy plane than the FX 100 and UCD 60. I doubt this engine will hover Showtime well and anything less than this will be worst. But if you install this engine in a Showtime, you will lost your guarantee anyway.
The only 3D engine I think you will be covered to a Showtime is a YS 110FZ, because H9 says 61-1.00 2-stroke; .91-1.10 4-stroke engine sizes.
Big gas engines are different. My yak's manual says to use an 100 to 110cc engine. I used a 3W 106 that can hold my plane with a good power source.
It seems the gas engines are more compatilbes with the planes they are designed for...
So, in the end, a glow engine 3D plane don't have any flight guarantee. They will cover some in box problems, but nothing more like that.
This is sad, but is what I can see of this manufactures... [

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