I used plastic ramps for my wife's mini in the past. But I can't seem to get my head around the engineering of the strength of that plastic either. I know I know- there is no way that they would be sold en masse with the liability unless they were 100% proven.
But still have a hard time. Old school thinking.
By the way - thanks for all of the replies. All very good info, insight, and perspective. (especially the mouth breather comment
)