My biggest concern with those frameworks is scale and speed. Anytime I see a framework that is trying to make my life easier I think it means more overhead. It'

My biggest concern with those frameworks is scale and speed. Anytime I see a framework that is trying to make my life easier I think it means more overhead. It's the same reason I don't use many of the asp.net components like the Update Panel and instead use my own hyper specific javascript or jQuery. To be fair I haven't put them to the test and I know major websites use them. It's mostly the perception I have of dealing with scale that keeps me away. There's also the fact that asp.net works so well for me and I'm comfortable coding in it. I haven't seen a compelling enough reason to switch yet. I still used other languages but the core is .net.