How 'bout this. I flew with a single stick radio for 20 years.
Finally, I wanted to convert to a computer programmable radio and update all my equipment. There were no single stick radios with the features and functionality of today's two-stick radios available.
I was forced to learn to fly two-stick (mode 2) while still trying to compete in race meets. This was a challenge !!! let me tell you.

It was like learning to fly all over again. Trial by fire.
I "trained" myself with several flights on a Sig Kavalier with a hot .40 in it. I then had to jump into Quickies and Formula 1's using my new two-stick. This was not easy. It significantly affected my performance in the local standings for a couple of years. I'm now used to mode 2 two-stick but it is still not as natural as the old single stick.
Randy Smith