We have been using an HP5000 for several years, just got an HP8000. The 5000 is good for a workgroup, a little lightweight if you have a lot of people sharing the printer. The 8000 is a lot bigger and heavier duty, should support at least 30 poeple depending on how much you print. Either can be configured with ethernet, multiple paper trays, duplexers, etc.
There are 5 of us attached to an HP8150N. We have used it for well over a year on the same toner cartridge. Don't know how many prints we have output, but it is considerable. Very pleased with output and performance. It is also network configurable through a web browser.