I find the leg press might have a slight advantage on thighs, but the one-legged DB squat hits the glutes a little harder. At least on my body. Hence, I keep both in the mix.
Now, once in a while, on my Powertec multi-station squat, I might do static holds with thighs parallel to the floor or do 1/3s partials/zones reps on that lower range. But I do this as a finisher and with very little weight to where it poses no lower back issues for me.