I'd go with the Phazer. Tektronix and now Xerox' print engine is far superior to HP's - infact I'm not even sure HP's Laserjet supports true Adobe Postscript level 3. The majority of their printers use their own proprietary engine which, while compliant, can tend to display some freaky weird renderings sometimes - especially involving Adobe Illustrator's more advanced graphical effects.
Phazer output tends to be more lifelike/saturated and less drab in my opinion.
On the other hand, if you're in it for the volume of output rather than the photo-realism factor, the HP may support cheaper toner consumables...
We use a Ricoh Aficio 3500 Photocopier with a true Adobe PS3 RIP at work. I've got nothing but good things to say about it, especially the output speed. If you're after an 11 x 17 image area with a speedy processor, etc; maybe you should look into a copier contract with a local distributor?
Even a blind squirrel finds a nut once in a while...