yah they suck , my cousin has one in his basement and like I went over there to mess around with it , I could bench all the weight pretty much all day , its like working out with rubberbands , the weight doesnt really kick in till at the top of the movement so all the strain goes straight to the triceps no matter what , and pretty much every exercise you can use all the weight cause it always kicks in at the very top of the movement , Curl , chest flys , tricep kickbacks , everything with all the weight.
Only upside I can think of is its a pretty good cardio workout , the weight sucks but gets you breathing after a short bit.