Kioti now tier V?

[perrypower]

I'm considering buying a new Kioti CK3510HST with loader and grapple. Does that model
have the DEF system? Service manager says no, salesman says yes---

I think you or your service / salesman is confusing terminology. The only Kioti tractor that uses a DEF system is the PX series.
The CK3510 that you are looking at has Stage V emissions controls on it (but does not have a DEF system). It has a CCRT (diesel particulate filter) that "catches" the "soot" and it will either passively or periodically (depending on how the tractor is used) "burn" off the "soot" in the filter.

Yes, this emissions stuff is annoying, but Kioti has actually had very few problems with these systems and I believe that have it "figured" out.