was on the fence for G2 stuff for years. went as far as powdercoating wilwood calipers in the past, and just running black w6a wilwoods.
on the SS brakes I upgraded to, I decided to try the G2 stuff.
not bad at all...
went out and bought like 4$ worth of 60 cent harbor freight brushes. so about 7 or 8 of em.
if done in very sensibly light coats, no runs. painting, via spray, gun or otherwise... usually goes in the pooper if you rush it. it was like a 2 hour job... maybe 2.5. I know I had to go somewhere last year and the wife was driving. we left about 3, and it sat till the next morning when I drove to meet the Camaro guys at a local cars and coffee...
truth note.... I didn't paint the back side of the caliper. just the half that can be seen with the wheel off. its not a show car and I doubt I'll ever do mirrors underneath for any various reasons. so for daily driving, track, autoX... it works for me.
it hardens and tightens up as it cures.