i have been flying about 9 months. i found that as soon as i was comfortable with controlling the plane, i got bored with anything that was not newer or harder. now that might sound cocky, but i havent mentioned how many stupid crashes i have had. a lot. a whole lot of repairing planes and getting really frustrated. i started 3d with a ucd foamy and then a great planes giles kit that i crashed after forgetting to pay attention. i am now on a funtana 40 with a saito 100 and it really makes it easier. my local hobby shop has g3 out so you can try it out and the owner was nice enough to let me play around 8 total hours in the last few days. i can honestly say that for learning quick reactions and reversing control inputs while inverted or belly-up the sim takes the cake. my knife edge has went from feeling really scary and awkward to feeling completely natural. if 1\2 hour a day of sim helps, 3 hours a day reeeealy helps.

it seems like it is easy to keep flying with out progression. i alwas end up at th field wondering what to try.. but get discouraged because things can feel so unnatural (like slow rolls or high alpha knife edge). as others have mentioned, the most important thing besides avoiding a crash is to keep focused on new things.