I have not used a large variety of leg presses. But of those that I have used, my favorite was the Cybex Squat Press. It is similar in design to the TDS model that heavyhitter32 owns.
The two pluses:
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Very smooth and low in friction. No belts, chains, pulleys, or cams to get in the way. Had more the feel of a free weight.
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Noticeable ascending resistance curve (due to the nature of the lever, the resistance rises as you extend your legs). In practice, then meant that the sticking point was further out in the movement, instead of at the start, where you are “coming out of the hole”. I think this is what makes it possible to get into a deeper position at the start, without risking injury to your low back.
Main negative: because of the leverages, you had to add a lot of plates to get a high level of resistance. I’m not a particularly big or strong guy, and yet I was putting up to 630 lbs of plates (7x45 lbs per side) of the thing, and getting 8 to 10 full range reps. Big strong guys could use a lot more. The designers seemed to understand this, because the weight horns were very long - I think you could put 12 or more plates on each side. But it got tedious loading and unloading the thing.
It looks like the Nautilus leverage design avoids the issue of inefficient weight utilization by using an extra long lever arm for the weight horns (relative to that used for the foot pad). The angle of the weighted lever also starts at a flatter angle, so it probably has a somewhat different rate of ascent for the resistance.