I have flown the H9 Texan 60 Arf with an OS 91 surpass and it was kind of crappy, even after changing props. I decided I was going to go for the OS1.20 Surpass but then I saw that the Saito 150 weighed the same so I bought that instead. I put a 3-bladed 14x9 prop on it so it should haul and easily hover at less than full throttle. I could almost hover it at full throttle with the OS 91 but it didn't have quite enough thrust. The Saito 150 only weighs about 1/2 pound more than the OS 91 and I only needed a little tail lead to balance it. Overall, the weight of the plane increased about 3/4 of a pound. It should end up at 8 1/2 pounds up from 7 3/4.