My local Gym Source got a Zero Runner in yesterday. I “ran” on it for about 15mins at a stated pace on the machine of 7:15/mile.
Pros:
-no impact
-you can get one hell of a workout
Cons:
-felt weird… didn’t seem to feel any more natural as time went on
-hard to keep a high cadence which segways to…
-may encourage bad habits: long stride, low cadence, foot landing ahead of the body
-foot continuously migrated forward on the platform, could cause irritation for some.
IMO a good short term solution for them would be to incorporate SPD-SL pedals into the platform to allow for the use of cycling shoes. A big thing holding this machine back IMO is the speed at which you can recover your leg in front of you which is limited by the generic platform/boot deal they have on there now.
Short Version: not worth it at the moment but a good idea. Wait for version 2.0. Those seeking low impact running are probably better served by Woodway treadmills (esp curve), Cybex Arc trainer, or aqua jogging at this time.