will X99 optimized ram work well for the z170?

It would be better if you change it, but a X99 optimised RAM will also work fine with your build. If you are getting this RAM cheaper than a Z170 optimised one , only then buy. Otherwise you are better off with a Z170 optimised one.
 
http://pcpartpicker.com/p/VC7G3F
Here, updated your part list. Added another Gskill RAM in same budget with higher speed. And changed your EVGA Power supply with a better one.
When you are getting a high end PC then always aim for a Tier 1 PSU. Seasonic PSUs are always the best, no competition to them. It costs you 10$ extra only with a much powerful, much stable and efficient PSU from a renowned Brand.
 


I dont have this ram im my country! and the X99 optimized ram is the cheapest
 

Try to get one with atleast 2400MHz speed. 2133MHz speed was found to be a little less for z170 in GTA V benchmarks
It made a 10 FPS difference on average just by adding a little speed.
 


I have heard that many times (that ram speed does not matter), but do you recommend buying the X99 optimized ram for my z170, it's the cheapes in my country (10$ cheaper) + it looks nice in my opinion.