If you have only an A1200 and you want it for serious use, then an expanded A4000 is a better option. But the sort of things you would want ie RTG graphics, RTG audio, video encoders are the sort of things that can be done on Winuae much cheaper, and faster still!
So keep the A1200 for things that work on AGA best ie games and paint programs, and use winuae for anything that needs RTG.
And to confuse even more, I have both and would never sell my A4000, with Cyberstorm 268060, Cv64, Indivision, FastATA,