I tried the HP colour laser printer and returned it three weeks later in sheer frustration. Print quality was lousy, it had to be reset every day, noisy...just more trouble than it was worth. That said, laser printers are still a bargain for B&W printing...hence why I went back to my trusty Samsung 1210.
I've used an HP colour laser (forget which model) and I too was not very impressed with the quality.
I'd recommend checking out the Xerox Phaser series. I believe they all come with ethernet but some of the better ones (7700) actually utilise a "500mhz G4 class" processor!! I've used the older Phaser 790DP quite extensively and I was generally pretty impressed with the quality even though it was only 8-bit. Here's a link to their newer models:
I have had a number of colour lasers over the years and I find the Tektronix series the best for speed and colour accurancy (and endurance too). I have upgraded to a new Tektronix printer and our old one now is for sale ....
I've an HP color Laserjet 2500n and have had no problems. It has to prep-cycle when its been idle for a while and does a self-clean cycle every so often but the quality is great as is its print speed. Even on plain paper. Blows away inkjets. It's Rendevous compliant. Only complaint is its size. It's a big beast.
We had a Tektronix 740 for about a year. I was not impressed at all, very happy when we got ride of it (actually I think it’s in storage still). I found it slow and used up toner fairly quickly. Make sure you have all the correct settings when printing or else you can do serious damage to it. We had to replace the drum kit (I think it was that) twice because of that mistake(exspensive).
Presently we’re working with a HP Color LaserJet 8550N. It’s been a good workhorse so far (1.5 years). Granted this was an $8000 machine and I don’t think you would have that in your classroom budget. It’s been good with colour matching and very good on speed and consumables. The only complainant I have is with the HP drivers. They don’t actually use PostScript drivers, just emulated PostScript drivers, so that has caused a few problems. It’s also a beast, as big as a photocopier. But I like it better than the Tektronix…. that reminds me, I wanted to throw it off the top of our building…