You know, after taking a look at these longer, my "favorites" have changed... I think the "best" fit is Drag Strip... It may just be A L's paint job, but he looks fantastic. Better than Hasbro could do for this mold.
Wildrider is the second, and it's almost a tie for first. The only thing that I think is a little off about him, is the red face. Ravage has a metallic red on everything, and although metallic red on the face would probably look terrible, the reds are slightly off (this is exactly how I'll paint mine though, I'm not bashing the sculpt or the paintjob) and that bugs me just enough to bump this guy to #2.
#3 is Dead End... because the Viper mold is a tad awkard, and I hated how Hasbro's Dead End ended up being a goth Sunstreaker, whose head is gigantic, and ONLY works for the Viper mold. The Valkfan Dead End head is just a
tad small to me, but as far as a head looking right on the slightly-awkward Viper body, I think he did the best job possible. The head sculpt is perfect for Dead End though, and I think it's a lot like a fat model with a beautiful face. Haha. I HATED how the Dead End "Sunstreaker" head actually had a mouth and was so iconic as Sunstreaker that I couldn't get past that. I've seen some people shave down the head and do bad mouth plates, but this one just looks damn good.
My #4, is Breakdown, and perhaps because I haven't seen Valkfan's finished body... The Viper, being one of my least favorite molds, ends up looking like a white Sideswipe with a blue head. And if I put the blue head on the Camshaft RSX body (after taking off all that hideous yellow), I'm not sure if it will look any better. I do think after putting some thought into it that the Mustang MAY very well be the best body, and since that's what Valkfan designed the head around, I'm going to hold final critique til I see his version.
But 3 out of 4 ain't bad, A L. Your paint jobs are fantastic, and I like that you are doing your own thing for your collection. In the end, it only matters if you're happy with it, and I hope you are. Please don't take it as anything besides me stating my silly opinion. Great photography, by the way. And as usual, fantastic head sculpts, Valkfan.

It's amazing what new head sculpts can do... They really bring these characters out of otherwise ill-fitted bodies that weren't
bad, but had a lot of potential that didn't quite make it. The bodies are actually good repaints... The Hasbro heads? Not so much. These really turn into the Stunticons without needing a bunch of paint on the bodies.
Do you think you could fix Swindle next? Haha. He has the same problem as these guys, taking an Autobot head that just doesn't work for his character, and you seem to have worked magic with the Stunticons.