Ultimate Marvel vs Capcom 3 General

You've seen more agile Sentinel players? Show me links.

Streams. I don't know if they uploaded the segments onto youtube.

Buying a stick will not in any way make you go from decent to godly in any kind of fighting game. A stick would only give a real pro an edge, for regular players the effect will be flat. Don't waste your money unless you are aiming for tournaments.

they make inputs much easier and quicker once you get used to them and it's harder to drop combos on a stick than a control.

ex: bold canceling into a bunch of moves on dante in mvc3 is goddamn near impossible to do reliably unless you have a stick or something better than a pad.
Another example is that it's easier to do the supers you want with characters like super skrull and taskmaster who's hypers vary depending on the buttons you push to activate them.