Due to the interest, I will provide additional observations from my film evaluation test. My top choice is Avery Nano-fusion. However, due to the complete lack of installers of this film, I believe the best option is Expel Ultimate.
The 3M Scotchgaurd (i.e., clear bra) film had so much orange peel I thought I must have been shipped a defective sample. The orange peel was in the film and not the adhesive. I suggest looking at the film in the installers shop for orange peel if you decide on this film.
Since the ultimate purpose of the film is to provide protection from flying debris, the best I could do to test this was to fire staples at the film at various distances. 3M Venture Shield showed the most damage. The other films seemed equal. Wish I had a BB gun for this test.
Dropping the two 3M films, I was left with Expel Extreme, Expel Ultimate, and Avery Nano-fusion.
Film specification - thickness in mils- (6 mil=0.006 inch)
Xtreme Ultimate Nano-fusion
top coat thickness 0.5 0.5 0.0
film thickness 5.5 6.0 6.0
adhesive thickness 1.6 1.6 2.0
Black Sharpie Marker Test - I drew a straight black line on each film and then attempted to clean it off. I used ethanol and 99% isopropyl alcohol on a rag. I did not saturate the rag. I put the rag over the opening in the alcohol bottle and then a quick flip of the wrist to wet the rag. The black mark came off. However, what surprised me was that the Xpel Xtreme film dissolved. If you go with Extreme make sure you follow the specified cleaning directions.
Now the decision is between Expel Ultimate and Nano-fusion.
Self Healing Test – I used a bristle brush to create observable swirls in the film. Both films self-healed and the swirls where gone after a few hours in the sun. In a previous test I got a bit carried away and used a pot scouring sponge and really roughed up the surfaces. The two 3M films stayed damaged. The Expel Ultimate actually cleared up a bit but would have to be replaced.
Film Surface – The ultimate has a 0.5 mil clear coat topping. This gives the appearance of a glossy surface. However, the surface is not slick. Dragging a finger across it feels like dragging your finger across an un-waxed car. The Nano-fusion is the exact opposite. The surface felt very slick. In the Sharpie test I had to press down harder to leave a mark. My conclusion is that the Nano-fusion will not interfere with the presentation of the C7 body finish where as the Ultimate has it’s own gloss.
Clarity – both films showed no orange peel. The Nano was clearer and showed less distortion when looking at a printed page through the film. However, the difference was not significant to chose one over the other.
I have no information on long-term durability. Perhaps other forum members who have these films installed on other vehicles can provide this information.