I have a shine gt lip and it takes a hardcore beating with my car being as low as it is. I'm actually going to replace it with a ww lip. I like the look of the ww lip like it was ment to come on the car from the factory.
WW Lip hands down takes more abuse then any FRP or CF lip
I have run into things head on and also scraped plenty. Its soft flexiable properties allows it to just bounce back. As far as the height is concerned its only about a 1/4 of a inch lower then the OEM stock lip on my 91. In fact theres no need to remove the front lip the WW one just installs over it. The only complaint that I have is due to the weather here in the east the cold and hot weather seems to cause some expantion and shrinkage and the paint usually cracks on mine. I now just keep it painted with regular spray paint
I"m not where I can check for sure now, but my NSX is still the stock height with the WW Lip, sideskirts, etc.
If I remember correctly last year I measured & my front lip was 4 1/2 inches off the ground.
When I initially purchased the car it had some chips, then backing out of a driveway without a shaved curb (around here the curbs are rounded and some driveways that aren't shaved basically are where you drive up over the curb to get into them), it caught my lip and pulled it off the one side. I was at an angle. I haven't done that again.
I ended up having the lip re-painted with 3M chip guard over the new paint. It has held up well.
Even though I try to be very careful now days, I still notice I have some scrapes underneath. You have to lay down and look up to see them. Looking head on they aren't noticable.
Overall I haven't had any issues with the WW lip. It has held up well for me. It was on the car when I purchased it and I've owned it 4 yrears now. It has almost been 4 years since I had it repainted.