OK, here is my feedback on Rhino ramps; I purchased the 12,000 pounders ( gray in color) and I am really happy I did as I found out today that they have about 4 times the reinforcement ribbing underneath or inside if you wish over and above the 8000 pounders (black in color). This extra ribbing all touches the ground not only helping in better supporting and transferring the weight over all but also helps in preventing them from sliding when the car is climbing them as so many more ribs are in direct contact with the pavement. The 12,000 lbs weigth 20 lbs each and the 8000 lbs weigth 14 lbs each, with the factory built in hand holes they are a cinch to carry, handle, and maneuver.
http://www.blitzusa.com/products/lift/plrr12.htm
Now proceeding to perform an oil change with these is a charm and so much faster (compared to a manual hydraulic jack and a couple of 2-3 ton support jacks), the ramps lift plenty high enough to easily slide underneath and easily get to the oil pan and drain plug and even further as well to perform a visual inspection of other components. Extremely stable, not a twitch !
I accidently drop the old oil filter of course filled with dirty oil and some of it splashed all over one, once the car dismounted they are real easy to wipe off, clean and hose off, they look like new in a minute.
Real time saver and a real good buy; I strongly recommend them to everyone.
Remember for safety sake once up always put on your parking brake and chock the rear wheels also.
http://www.blitzusa.com/products/lift/plrr12.htm