My floor jack looks ancient, it used to be my father's, weighs a ton, but I can get the car lowered very slowly or very quickly. It is easy to modulate it. The thing is it takes about a bazillion pumps to raise the car, no pressure loss though.
That might be the HF jack commented on a couple times above. You'll see different opinions about Torin jacks, but I think that's partly because there are plenty of models, some of which must work better than others. I don't think you need to pay upwards of $500 to get a good jack though. For example, as I said I'm happy with mine and Ron says you can get that model for $99. I think I bought mine at Pep Boys for at least $20 more (+ tax vice shipping).
You can get that jack for 59 bucks--the car mags have coupons in the back, Road and Track has one second to last page in Novembers issue. For the money, it can't be beat, and when it explodes, I'll just replace it...I've didn't get the service plan, I've gotten three years out of this jack so far, and I'll replace it when it goes--currently it works just as well as the day I bought it. I have a backup jack--craftsman--but it's heavy, so I rarely use it, even at home, the HF is much more convienent.