For those of you with the new Zforce 500 HO can yall help answer a few questions.  Does this unit have enough pep to cut up on the trails?  Power slides, donuts etc.  I am torn between the 500 and the 800.   Like the cheaper model but don't want to kick myself for not getting the 800.  Thanks

I have used both and they both serve their propose well.
I think Dirt Traxx summed it up well, Rework the clutching, fuel controller and pipe and that 500 comes alive.
I just got the Z550ex long enough to try it. even better, I didn't lie the tippy nature of those 50's

I have the 2016 zforce 500 and I like it great . It has all the power I need with a top speed of just under 60 mph , as far as tearing up the trails it will side drift out of the turns when you want . As far as climbing hills I have not gone up one yet that it lacked power for . My son in law has a 800 rzr and we have lined them up and yes his has a little more off the line but it is minimal .Mine is the 50" trail model and I don't find it tippy .               
  Price was a factor for me and we have a lot or tight trails so the 500 is fine . If I lived where are a lot of open trails and or sand dunes then yes I would look at the 800.

I have the 2016 500 Z-Force so far it has been a good machine but it's at the shop because of the water pump keeps leaking from the weep hole but does not lack for power and I have had in mind to 60 miles per hour with throttle left 2go