I just pulled my spoiler. Thanks for the great thread.

I have had mine for about a month. It started leaking a line of what appeared to be a combination of mud and calcium down the outer trunk lid. When I pulled it I could tell it had been "repaired" before. I didn't have the rust as shown in the original post, but the repair had been done poorly. Sealant (not silicon) was in all the wrong places.

Some advice from a someone who spent 25 years as a plumber keeping water from getting into places it shouldn't be.
1. Put the orings down in the recessed openings, not around the threaded studs. That will insure they seal properly to keep water out of the trunk.
2. Put silicon only around the flat portion of the spoiler that will touch the trunk lid. Silicon around the rubber gasket, bolts, orings, etc. will not keep water out of the assembly, which is the whole goal.

I wish they would have designed a way for the water that got in around the rubber gasket to drain away in the first place. What they designed was a moat around that gasket.