ORIGINAL: gaRCfield
Mixes are a bad idea at this point. The plane needs to be properly trimmed first, which includes a battery of tests to determine if things like CG, incidence, dihedral, differential, etc. are all set up correctly. Using mixes to fix things that are mechanically wrong with the plane is not the way to go.
Dual rates sounds cool. In reality, we all forget to flip the switch at some point, forget where the switch is, etc. (hopefully) until we've been flying for a while. Set the plane up on low rates and fly it. Get comfortable with it, learn it. Then you can say to yourself "hmm, I feel like it should roll a little faster" and at that point you might just want to increase the current rates, and not have dual rates.
Dual (and triple) are really for setting a plane up for 3D and for competition. I've got two competition planes and really only need dual rates on the rudder for big rudder moves. At some point you'll learn some throttle control, and find out that you can increase/decrease the sensitivity of the plane at different speeds, attitudes, and how the prop wash is blowing over the plane.
This is very poor advice, especially when doing a maiden flight for a plane. There has been more than once that I have taken a plane up on a maiden flight and found that the high rates make the plane almost uncontrolable and the only way I was able to fly it back in for a landing is by switching down to low rates on the radio.
Dual rates are NOT just for 3D and for competition and recommending that they are is almost a bit snobbish. I don't fly 3D and I definitely don't compete, but all of my planes are set up with dual rates. There are many reasons why dual rates are good for us "every day fliers", but here's the main reason I do it. On many planes it's nice to have a lot of throw on a control surface, such as the ailerons, when in the air. But when it's time to land that much throw can make it a bit "twitchy" or sensitive when making an approach. However, by simply switching to low rates it's easy to bring the plane in for a landing.
Ken
Ok, reading the original post: the OP is flying a basic .40 size trainer. There is no evidence that he has even flown a plane before. Where did these dual rate figures come from? Why is there a rudder-aileron mix - because you decided it needed it in the air, or because it looks cool or you saw others doing it?
Ken, you were the one that beat it into my head 6 mos ago that a basic 4ch radio was all you needed to fly a trainer, and that I shouldn't be playing with my 'fancy computer functions' or whatever while learning to fly a plane. That is like the best advice anyone has ever given me, and it came from you!
I agree I 'mis-spoke' when I said '3D and competition'. I should have said 'more advanced aerobatics'. Flying the pattern, doing figure 8's, rolls, loops, stall turns, cuban's, and even knife edges, can all be done on a (Nexstar) trainer on the suggested SINGLE rates suggested in the manual.
If we don't know that this pilot has even ever flown a plane, how can you suggest he be THINKING about dual rates, let alone using them???