How do you guys feel about Pneumatic resisitance?

I go to a gym that has a section of Keiser pneumatic machines/squat racks, been doing a lot of work with free weights with air resistance attatched latley.

For example for box squats i have a belt thati attach the air resistance cables too so it pulls directly down on my hips, along with a barbell on across my shoulders ofcourse

Seems to keep all the resistance constant and not let me depend on momentum as much to complete the rep

What do u guy think?

No one?

I tried them once, terible terible invention. Felt way too spongey.