Caution long post. First half my experience. Second half my thoughts on the products.
I recently acquired some 4 pot brembos. The standard flat black finish didn't do it for me, so I went about changing the color. Decided on silver to match my Ingot Silver GT, as I wanted something to contrast with my black wheels but not be too flashy.
I decided on the G2 paint system. G2 is a two part epoxy paint that is tough, doesn't require a clear coat, and can be brushed on. G2 recommends that their metallic colors be sprayed on for best results, and they recommend the use of a Preval spray system
For prep I sanded imperfections on the caliper smooth with 100 and 300 grit sanding blocks, then roughed up the entire finish with a red scotchbrite pad. I removed the crossover tubs and taped the holes, the taped off the bleeder nipples and piston area. I cleaned the calipers with brake clean (they are brand new, so no difficulty there), and hit them with a solvent prep-wipe before spraying.
I had planned on painting the front and rear calipers silver, but due to the Brembos already being off the car I was going to spray them first and then the rear calipers later. The G2 paint system provides 3.5 ounces of paint and .5 ounces of hardener. This is to be mixed at time of use. I measured approximately 50% of each with a syringe so I could save some paint for the rear calipers when I got around to spraying them. G2 states that 4 ounces of paint is enough for 4 calipers or two calipers and two drums.
The first attempt at spraying proved problematic. The Preval sprayer has a tendency to launch large paint splatters on the surface if tilted at an angle greater then 20 degrees, and the G2 paint runs like crazy if sprayed too close. After the first two ounces of paint 1 caliper was covered in uneven splatters, and both calipers needed more paint for total coverage (I am painting the entire caliper, not just the visible areas).
I decided to try again, and after curing the calipers in the oven, I wet sanded the imperfections and roughed up the surface.
I mixed the remaining paint and made a second attempt. I made sure to use the filter tip on the suction tube included with the Preval sprayer (the first smaller container I used did not have a filter on the pickup tube). After experiencing significant runs on the first attempt, I stuck with numerous light coats. Preval and G2 say to spray from 6 to 8 inches...I'd say closer to 6 inches with a light coat is ideal. Any closer and you get runs, any farther away and your just filling the atmosphere with paint due to the force and spray pattern of the Preval sprayer.
After completion of my second attempt I was satisfied with the results. The finish is not smooth, and I think that is a combination of the spray pattern of the Preval and an issue with over spray, due to the proximity of the calipers when spraying.
The official review
Consistency: Based on my experience and what I've learned with google searches, this product has a tendancy to run and drip. I recommend anyone using this product to stay with several light coats. In my second application I did 6 or 7 light coats.
Texture: In a hidden area of the caliper I applied some of the paint with a brush. The silver paint is an very metallic, and just did not look good when brushed on (visible brush strokes, uneven metallic flake). Non-metallic colors would not have this issue. Using the Preval sprayer I achieved a uniform texture, but having sprayed the product from farther away and using light coats, it is not very smooth. I'd almost say the paint dried with a hammertone finish which looks kinda cool in its own right, but is not something most people are going for. Part of my issue was overspray, and in hind sight I should have moved the calipers much farther away from each other then they were. G2 says the product is self leveling...I'd say no more then any other liquid paint. If brushed on, expect visible brush strokes unless great care is taken.
Color: The silver metallic is beautiful, and has a ton of metallic flake. Its a pretty good match to Ingot Silver, and should match any standard silver color well. G2 says their paints dry to a high gloss. There is definitely a gloss to the paint, but its nothing like a clear coat. Its certainly glossy enough for a brake caliper and feels like it will repel dirt well. Very pleased with the color.
G2 says 1 can does a whole car. For some colors I'd imagine this would be true. I'd also imagine that if you painted the calipers on the car you'd use a lot less paint because you'd only be painting the visible surfaces. However, with the light silver paint over matte black, it took about 3 ounces of paint for complete coverage on two Brembo 4 piston calipers. I ended up using all 4 ounces because I was not ready to spray the rear calipers at the time, and once mixed the G2 paint has a working life of about 4hrs. If you have never used the product before, and are spraying 4 calipers, I'd get two paint kits. An alternative would be to get an engine paint kit also sold by G2. These are the same exact paints and colors, but sold with more product in each kit (at a slightly higher cost).
The Preval Sprayer
Ease of use:
There is a learning curve to this product. It took me 2 ounces of paint to figure out how to use it well. Don't treat it like a spray can...its not as easy to use. You cannot tilt the product at extreme angles otherwise the paint can drip out of the bottle AND the sprayer will launch large globs of paint through the air. Keep the sprayer upright and manipulate the item being sprayed to achieve the best results (not easy when you're painting all sides.
A trick I learned quickly was to have a loose piece of cardboard in one hand while spraying, so the Preval sprayer could be primed with each spray. After spraying all the paint drips out of the pickup tube and on the next spray you'll be greeted with several seconds of air before any paint exits the sprayer, and the first bits of paint to leave the sprayer will be big globs. To avoid this keep some scrap cardboard nearby to prime the sprayer before each pass.
The cans on the Preval are small, and upon initially observing the Preval I thought I'd be blowing through cans left and right. The good news is each Preval can seems to be able to last for about 3 to 4 ounces of paint.
Verdict? Use VHT caliper paint and clearcoat. Cheaper, easier to apply, and probably just as durable. Each G2 kit is $40. The Preval value pack I ordered on Amazon was $19. After factoring two kits of G2 and the Preval unit, I'm at a $100. I could get the calipers powder coated locally for the same price. Lesson learned.