What class are you flying it in? I have flown them for 3 years now. Flew to 4th place in Masters this year at the NATS with a sub 10lb NB Engineering Mantis. This was a nice setup, but I wouldn't go much more than 10lbs 4oz if you plan to fly higher classes. On a nice 65 degree day with no wind it will comfortably fly FAI, but if its in the 80's with high winds, even with 25% Nitro and a 17X12APC it would be marginal in FAI with the vertical snaps over 10 1/4 - 10 1/2. I'm turning about 8200 on the ground with the 17X12. This will be my last year in Masters, and I will be changing motors after this year. The reason being on a vertical upline snap in mid july, when the prop is really loaded it will mush out of the snap (this is lack of torque from the big 2 strokes). The 1.60 FX is a little better, but they still do not match the torque of the 160DZ, or especially the electrics. Classed up through Advanced you can comfortable get through with any setup with the OS 1.40 or 1.60, but on a really hot windy day with a heavy airplane you will be right on the edge in the upper classes,

Just my .02 worth,

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