There is another thread that discusses the 3M Paint Defender product but since you asked and since I tested it this past weekend, I'll chime in. I tried it as an experiment before spending the big bucks on Xpel clear film. The product does dry to a very clear and glossy film and, if you follow their instructions, the edge looks the same as clear film so that's all good. However, it takes several hours to dry and, even though I vacuumed and cleaned the garage, applied it with the garage doors closed and avoided working in the garage while it was drying, it still picked up some dust before it dried. On a dark car like mine, the dust showed (it made small imperfections in the surface) and I was not particularly pleased with that. Another thing was it was difficult to get in the cowling areas on the front of the car with the right amount of product. I had a sag in one of the vent cowling areas so put it on lighter on the other. Surprisingly, the sag dried clear and nobody would ever notice it unless it was pointed out. I decided that I still want to use Xpel so peeled the 3M stuff off. It removed easily for the most part except for a couple of areas - where I sprayed it thinner to avoid sags in the tight spot of that cowling mentioned above and another area under the
oil cooler area (the very bottom of the body) where I didn't get it thick enough. If it is too thin, it won't peel off because it isn't strong enough and I had to remove it in very small pieces and use Windex with ammonia to dissolve some of it as well. So, bottom line is that if it could be applied in a paint booth or other dust-free area, it would look better (at least on a dark color where it shows more). Also, now that I've done it once, I think I could do a better job the second time. It would still be a challenge to get it the tight spots with enough product without creating a run or sag. Another poster in the other thread mentioned more, lighter coats than 3m instructs which might work well. The trick is to get it on thick enough to provide protection but without runs and sags - unless you're an experienced painter, that is easier said than done. I think I'd rather spend the money once for Xpel that will last for many years rather than have to deal with this more frequently. I assume it would last longer than the one year they advertise since these cars aren't exposed to the elements as much as other cars, but still not a fun project that I'd want to do every few years.
Regards,
Kevin