If you are designing your game well, you shouldn t have problem
Of course if you design it badly, you will have more problems, but in the end you will also have problem in a more powerful engine, just at an higher point. And since for so many reasons you want to design your game well anyway, it is not a problem.
Often people says "C2 should not be marketed towards non programmers", when in fact non programmers will do just fine, as long as they think well about their games (Should I verify all those collisions? Should this AI be enabled? Am I using the functionnalities correctly?)
If someone has problems with only a few ennemies on C2, either he is doing too many useless verifications and actions, or uses a bad graphic card driver (or both), while fusion is maybe more tolerant upon those points. We can help when you have problems anyway so you understand how to work in a better way, of course if at the end you want to use fusion, use it.
Reminds me of the user asking for all little secrets about C2, there isn t really secrets, just don t do useless things, learn how C2 works (manual, eventually tutorial but keep a critic eyes on them, some are really not that well though), and also learn to organise your events, so you can easily correct bugs and optimise (I have seen some event sheets, that no one could understand long term wise)
Also node webkit and chrome performs the same (chrome has sometimes better performances though), but if you go with "game in a browser = shitty game" you are wrong, they are just easier to do so people do them more often.
The html5 weakness is more mobile, but on PC this is not justified