anybody know about 2-post hoists?

I splurged and bought a Rotary 10,000lb assymetrical 2 post like what you are describing. As others mentioned above, the asking price is nearly half the price of a new Rotary lift. Mine cost me about $5k installed. I looked at the other brands, like Atlas at Greg Smith, as well as Bend-Pak and others. I had the money and my wife's only comment was "If you're going to buy a lift, get the best rated one out there. I don't want you standing under a lift that you skimped on".

Truth be told,... I think the Atlas, Bendpak, and some others are fine. $2500 for a ten year old used lift, that you don't know how it was treated seems high! I remember seeing some used ones before I bought mine and they were running $1000-$1500.