When you have the needle set on your engine so it's running just slightly rich from optimum, you fly the airplane.

First thing to look at......... take off performance. A couple of things.........
Don't SLAM-IT-AND-PRAY. Line the airplane up on the runway and advance the throttle steadily. It ought to take you 4 or 5 seconds to get to FLAT OUT. The airplane should start to accelerate right away and the acceleration ought to increase with the throttle. That's pretty intuitive, but remember, if you've got the wrong prop for the airplane, it might not. Did the airplane accelerate with the throttle? Keep it in mind but look at how it climbs out. And how the engine comes up to top speed.

With the airplane at altitude, check out the throttle response. How does the airplane slow down and speed up in response to throttle position? Now, hit wide open throttle and see how it climbs straight up. Once up there, chop to idle and see how it dives at idle.

Now throttle back to landing speed. That should be about three-four clicks from throttle STICK (not trim, stick) all the way closed. After the model settles into that speed, how does that speed feel to you? Fast enough to be safe for landing? Too slow for safe landing?

So land it at whatever throttle gives a safe landing speed. And think all of it over.