both the nammor and KM are excellent, the advantage of the nammor is that it comes with the nammor hose which is my favorite.
you can pick one of those up 20% off this week since its the anniversary sale.
I think the KM is a better hookah, constructed old school and sturdy. I think that there are a few videos on here comparing the two.
As far as the chiller goes, you will get cooler smoke from putting ice in the base.
If you do add ice to the chiller you should also add ice to the base. The chiller makes a small difference almost unnoticeable. some will say no difference at all. I say it makes a small difference.
I have a chiller on my KM, i rarely use it. It still looks nice though.
hookah-shisha actually carries my hookah here is the link