I switched to full squats from quarter squats...
I feel a whole new kind of soreness now..
Although, on the first rep of my first set, I let my knees go past my toes and it was quite painful coming up. I didn't make that mistake again and I felt no knee pain or tension.
Someone said, "the only muscle 1/4 squats exercise is your ego," which applies to me quite a bit heh. I could do about 215 in 1/4 squat but if I do full squats, I'm struggling with 135 by the time the end of the 3rd set rolls around.