My story; I was jaded after pre-ordering OOTP 12 ( in Feb of 2011 ) and waiting forever. The product was solid but I never really got into it. I had just finished my first season playing every game, after toiling away customizing my fictional league when I received the email that OOTP 13 was being released. I hummed.... I hahhhhad and then bit the bullet and bought the new version. For the first time ever I imported my season and hoped that I wouldn't have to start over again.
The answer; of course not. The import was flawless. And I agree with what has already been stated in this thread, that RTS is the greatest addition ever. Immersion factor increase by 140 maybe even 300.
Thank you!