Re: Hookah sizes comparison
Height doesn't matter much once you get past the "table-top" size hookahs.
The two main things you need to look at is the thickness of the stem, and how deep it reaches into the vase. Ideally, it'll be 2-3 inches from the bottom so you can have an inch of water cover it and still lots of room for smoke.
It should also be thick enough so you can easily fit a pencil inside. If not, it's going to be restrictive.
It'd ask what brand you're buying. You can get a good MZ for $75 or KM for $90 if you are looking at mid-sized hookahs. Either one will smoke great. Just don't overpay for a chinese hookah with a short, thin stem.