I got the cart Bermuda showed in the OP. It's pretty sturdy, and not too heavy to deal with when folded up.
I've seen it on Amazon for as low as $79, but I got the last one from a seller and it was just under $70.
The R8 cart Mr. Compactness linked looks nice, but doesn't seem to be any larger than the one I got. I like the wheels on it though.
Shedboyxx, the flat base hi-hat stand I have is the Ludwig Atlas Classic.
Very sturdy, comfortable to use, it's responsive and light weight. It doesn't sway when playing 15" hats with gusto, and it folds up and down pretty easily.
The Ludwig Classic FB cymbal stands are great too. Very sturdy, light, and for me the adjustable height rubber feet are genius.
Superb wing nuts on all these Ludwig stands as well (an overlooked part with some stands).
They seem to be as expensive as DW's 6000's, or maybe a little more. The DW flat base stands are great too, and they have memory locks which I use.
Gibraltar flat base stands are sturdy and work really well too. The Gibraltar Brake Tilter is very nice. Gibraltar stands have nice wing nuts that work smoothly as well.