Well the SNES pad was perfect for the moves, I hardly ever missed one. A SNES pad would be a dream.
The standard 360 pad is a bit dodgy for XBLA Hyper Fighting and Super Turbo Remix though.
I have my eye on the £35 fight pads. Hopefully they work well enough for the price - I'm a pad gamer, not a stick - 99.9% of my time with Street Fighter has been on a pad, with a tiny % on a stick in the arcade, so a good solid pad, like the fight pads will be (hopefully) should be good for us console gamers who want the moves to work but
CBA getting used to a stick.
The DLC for STIV will be in the shape of different costumes for the fighters, released in various packs.
5 characters per pack, released a few weeks apart.
The exclusive DLC is simply 5 of these costumes, probably the first pack, and the bonus is you get it a few weeks before others can buy it on XBL. I can't see it being something completely exclusive to the collectors edition.