I just spent 2 nights in MUC, happy it wasnt 3. It was raining pretty uch teh whole time, but I still got everything I wanted to see in

Theres nothing IMO worth seeing in FRA, Mainz was alittle interesting but I did enjoy walking around the Old (rebult to look old) section of MUC. The Residenz can kill 2+ hrs , but my suggestion would be if you were never there go to Dachua, I spent 4+ hrs there, very informative and worthwhile (and it wasnt the 1st camp Ive been to.