I have them. I was going to make a diy on install, but then thought it was easy enough for the average joe (like me)... so I didn't. =D But if you search I think you'll find more pics and some others asking questions about them.
But they are much cheaper, made in the USA and work. enuff said. =)
What really matters is the mounting hardware and mount points. The surface area of the slider isn't really all that important. The T-Rex pucks look like they might be a little less likely to dig in and snap off, but if the mount if flimsy it won't matter. Also, if the mount point is in one of a few key areas, the sliders can cause more damage to your engine and frame than the wreck would otherwise.
Does anyone have a picture of the T-Rex sliders with the fairings off?