Well, as you know, Roors are the sheit! Just make sure you get the .de (German) version, and not the cheap knock-off US ones. Check out everyonedoesit.com, as that is where I got my last two Roors from and you can't go wrong there.

As for what you are considering:
Roor Custom Bong 3.2 - Red Mini Master - Online Shop
Roor Bong 'Zumo' 4.2

Not exactly sure which ones of these you were looking at, exactly, but with the Zumo, you are going to need to spend a bit more than $200. You also need to consider shipping as well, so it will run a bit over your current budget.

Both of these are pretty bomb. In fact, most all Roors are, but it all depends on your needs and wants.

And, yea, if you have some more cash, definitely go with a diffuser as well. I just got one from EDIT, and it *really* made one hell of a difference!