Buying a new hookah is always an exciting event, have fun with it! In my opinion the best hookahs for the money are Khalil Mamoun or Mya Sarays. Hookahcompany.com has a nice 28" KM, as for Mya Sarays you really are limited to a few models based on your budget, and since you're looking for a medium sized hookah, my recommendation would be their acrylic hookah, they're very durable, look nice, and smoke beautifully.
If you are interested we'll be getting the Mya Saray acrylic along with a few other Mya Saray models within the next few weeks, you'll also receive a 15% discount by using the hookahpro.com discount code "hookahpro". Look around; read some more reviews, and see what kind of hookah you like, I'm sure you'll end up with a Khalil Mamoun or a Mya.
Hope this helps, good luck!