I second this question. I have been looking at these but have been scared of by the fine print that no hardware comes with it (at least one I looked at) and that modifications might be necessary. I want perfect fit and finish.
My experience is this:
The outer most holes, in the trunk lid needed to be modified a bit (it's just a car).
No hardware. I used three M6x1.0 bolts and M6 washers. No biggie. My advice would to be to get a few M6,1.0 threaded studs and blue loctite them into the spoiler, for ease of installation.
I used a "D" profile foam westherstrip on the bottom raised profile of the spoiler. This mitigated any potential rubbing if the spoiler on the top of the quarter panels.
The wickerbill came with 9 countersink screws, in chrome. I swapped them out for M6x1.0 black bolts and black dress washers. I plan on having it CF dipped, soon.
If you install the winglets, on the bottom of the bumper, you will have to drill three holes, each, fir either push pins, or bolts and nuts. I did super red 3m adhesive tape and bolts.
The diffuser had two tabs that didn't like my bumper. A quick file job took care of the issue...then it hopped right on.
Overall, I'm very satisfied with the product. If you can deal with these issues, it's a great upgrade. I constantly get compliments.
Hope this helps.
Bob
Riverside, California