Different Leg press Machines, which are better?

[the*_Rat]

First off, I would like to say that I use squats as my primary quad exercise; However I like to do a few sets of leg press afterwards to solidify everything.
Some leg press machines are made to have your feet positoned vertically, while others are almost on a 45 towards you. Which one is the safest and more productive? I know using the vertical is harder, as it will take off at least 100lbs of strength.

 

[the*_Rat]

bump

 

[blood_drinker]

http://www.ast-ss.com/

Go to training exercise at the top.
Then click on legs.
It will then go to a page full of links explaing all leg machines and the pros and cons and some other commentaries.

Hope that helps.