I took the plunge and ordered the RCBS rockchucker supreme reloading kit, but I have no bench and limited space. I was wondering what everyone who is short on space uses for reloading benches. I was looking at the Frankford Arsenal unit(page 45 of MidwayUSA catalog), but was wondering if I would be better going to Menards or Home Depot and just picking up a collapsable bench that I can stow when not in use.

you can clamp it to a Black and Decker Workmate. Or make a small plywood top for same with a 2x4 cleat on the bottom. Clamp the cleat in the jaws of the workmate. Put the press on the top(bolted or clamped).

Oh, yeah. There's all sorts of ways around the space problem. One thing I do at the range (read: the forest) is use a piece of plywood with an L-bracket attached so that it slides down in the window slot, then a post on the fron of the board that extends to the ground.
Rather ingenious, if I do say so myself.
I have an extra single-stage that I just c-clamp onto the board, set up my scales, and run go.
Great for load development.
Not that this is exactly what you're talking about, but another example of how to use space well.
My father for years had a desk with a pullout writing platform on the front, he'd pull that out and replace it with a 2x8 about 2.5' long, with his press bolted to it.
Do his thing on the desktop, when done, pull out press and board, replace writing pad.
Worked like a charm.
I've often thought one of these in-the-wall ironing board jobs would be a great rig. They come with shelves inside, where you could keep your bullets, powder, scales, maybe everythign but the press. Pull the "ironing board" down, clamp on your press, voila. You'd need a leg of some sort, since these aren't built for that sort of strain, but that ain't no biggie; just hinge it so it hangs along the wall when closed up and comes down to the ground when open.
You could even mount a second one below it, just for storing more reloading supplies.
Damn, wish I didn't have a garage full of space, I'd do just that!

Bucktail...
The portable stand Midway sells works fairly well. I used it for the first six months of handloading. Sometimes I had to place my feet on the pedestal base to keep it from rocking a bit. Not bad, though.Other than wobbling just a bit under heavy pressure, it is quite tough.

Press(s) on a board, and "C" clamp the board to where ever you are.
pic of 5 presses on a board