I've been researching this same topic & am trying to decide what to get. This topic has been covered in a lot of detail in a number of threads on one of the Corvette forums (please, no jokes about sacrilege). Go here:
Corvette Forum search page , type in 4 post lift or four post lift in the Search For box, click on Archived Topics in the Data Set box, click on Post Bodies in the Search In question, then click Next, to display a listing of the threads. One of them has pictures of a recent install of a Stinger lift and there's a very very long thread started by a guy who had one corner of his lift collapse (deferred routine maintenance apparently caused the collapse).