Well depends on what you want to do... For just hovering and simple forward flight with the flat blades, I would suggest going to a 1000-1200 3s1p lipo pack and 8t 370 motor, which the motor eflite sells for 10.00 that's what I am running and I am getting 25 minute flight times. The heli is nice stable with this setup, I think that head speed with the flat blades seems to really make a sweet spot for hovering...

Now for more aerobatic flight I would suggest the 9t 370 motor and the same lipo with a the semi-blades... I really dont care for the semi blades so far, just seems to make the heli less stable for a hover as I am basicaly a newbee to micro-heli's I have about 6 months experance on these micros and a lot less on then that on the blade.

But that said I have tried all these setups on my blade stock battery with flat blades, enhancement kit with the 9t motor lipo's and semi blades, 9t motor and flat blades, 8t motor and semi blades and the one I am running now which is a 8t motor, flat blades and lipo's which to me is the best for me right now. I get great flight times and she really stable of course I also have the gain turned up on the gyro as well. I think it's all in you skill level and what you want to do with the heli. Myself I just enjoy slow flight and long hovers for right now.