I was hoping to read a few other replies on the subject of '75 and '80 models from the Maico experts. I owned an '80 model MC250 Mega 1 for a while and didn't think it was too bad. It felt a little weird in the handling department at first , because it was very high at the headstock and had long forks. It also seemed to have too short of a swingarm and wanted to wheelie too much when you didn't want it to. I fitted an '81 swingarm to the bike and it made it handle heaps better.
Regarding the '75 Maicos, they seemed to be an in between model with basically the same frame as the '74, with some changes made to accommodate a new 5 speed motor (which apparently had some gearbox issues which were sorted out for the later AW's).