Nahh, looked fine man, and I lift around competitive powerlifters, 3 who can squat over 600 and 1 who can squat 1000. Nothing wrong with those squats.
I don't think the forward lean is what one should be worried about so much, but whether or not you maintain an arch or at least a flat back. The guy that squats 1000 at my gym uses a slightly wider than shoulders stance with only moderate toe flare, but his back easily goes down to 45 degrees or more, but he maintains at least a flat back. I don't feel an arch is a must so long as you can keep your back flat.
Ever see Dr. Squat-Fred Hatfield's +1000 squat. Narrow stance and an assload of forward lean, but his back is still flat.
I guess it depends on the goal. One guy may only be impressed by an upright ATF squat while another guy might not care if it's just below parallel with alot of lean. Either way, if it's over 400lbs then the person doing the squatting is still strong imo.
When I squat for heavy weights I like to lean forward enough that it becomes a combination of back extension and leg drive when I come up. In order to feel like I am getting my back and hips into it I have to lean forward a fair amount so that I can feel my back pushing the weight up as well as my legs pressing it up. If I stay too upright it places most of the stress on the quads and I can't squat as much because I am not using the hips, glutes and hamstrings to there full potential.
But since you are after quad size, I still don't think you were leaning too much at all. In fact, if I were trying to squat that weight I would look more like the last rep than the first because as your legs fatigue during the set you lean forward more to bring the powerful back muscle into play to get the weight up.
Excellent squatting regardless of style used though.