Roor percs are only made by Roor USA, out of Los Angeles, and they dont get spread out but for a couple hundred miles for the most part.. (San Fran-> San Diego). It's extremely rare to find them outside the area, and they will be expensive.

PHX makes a killer piece, but IMHO don't really like the perc design. For my style of smoking most of the time it has a little too much drag, plus cleaning the multiple percs can be a bitch if you don't do it immediately after a use or a couple.

I think the most important part of the bong is the glass on glass seal (instead of a rubber grommet), which limits you to only a handful of manufacturers. Even the no-name glass on glass bongs are solid pieces for the most part - the seals seem to be of similar manufacture and quality. Plus you can interchange bowls and downstems/diffusers most of the time..

Speaking of obsession....
I have 7 (!) bongs (and 5 or 6 other glass pipes) (3 Roors, ADS, ZOB, and 2 more no names). 6 of the bongs are Glass on Glass and for the most part, I can't tell much of a difference between the seals of the roors, and the others. The Roors are straighter on their bases, don't wobble at all,are more symmetrical (like with the ice pinches), and the "welds" just seem cleaner and more perfect than most of the others. Probably due to the brand name, and a little better quality control. But my $65 ZOB 18" 18mm straight hits as good as, or even better, than my $250 18" 18mm custom Roor bubble.