I just started using Construct a few months ago and was impressed by its general usability, the speed of new releases, and by how active the forums are. I have never used MMF2, but I have tried gamemaker and Construct is a LOT better. I kind of agree with the suggestion not to start a big project. I would suggest to make small programs that test different features you want in your program. If you can produce all features individually, then try implementing them in a larger program. Over all, I would say to try it out and if you find a bug, report it. Then wait for Ashley to work his magic and continue.