Damn I guess I've had them on for close to a couple of years now which is crazy to think about.
They're still on there and doing their job just fine, no issues so far. I could probably take them off and reapply the double side tape to keep them fresh but they seem fine for now.
Here's a current photo of my Coupe - got a big ol' crack in the windshield that I've yet to replace but at over 2 years of owning my Coupe I've got no complaints other than a weak ass windshield lol.
No real update from the last design and they're holding up well enough on my Coupe. Need to figure a better way to bolt it onto my trunk though - needs to be more weather/water proof
1. Touch up paint is the easiest way to prevent rust imo
2. I would use a rubber washer if you can
3. 3M tape shouldn't damage the paint and can work to weather proof as well
4. I would use color matched bumper plugs even though they are kind of spendy
5. Can't talk on this point unfortunately
Yes, you could go the route myself and a few other people have done which is to install the SI diffuser and then get a custom exhaust installed by a shop.