The South Bend pressure plate isn't too much stiffer than stock. I've got a south bend full kevlar sprung clutch, and RPS flywheel. The clutch is a 6 puck job, so you do get a bit of judder sometimes as it engages as some of the pucks grab before others if you see what I mean. It tends to do that more when it's hot, and if you don't use many revs when pulling away. Mostly it's fine though, the pedal pressure is pretty much exactly like stock.
The amount of rattle I get at idle varies, sometimes it doesn't rattle at all, sometimes it rattles quite a lot. It seems to rattle more when hot though. I also get a rattle when I accelerate in a high gear at low revs which I find more annoying than the idle rattle, but It doesn't bother me too much and I much prefer the engine response with the lightened flywheel.
This link has been posted before I think, and has some useful info on different clutches.