I had used Brother 7820N. It worked fine, excellent interface, very easy and fast network faxing, but it was very demanding in terms of supplies. In addition to cartridge it has a drum, each of them has to be replaced separately. It only works well with brand name drum and cartridge. It didn't work with refilled cartridges at all, and "generic-made" drums and cartriges resulted in very poor quality printing. Brand-name cartridge costs $50. It only costs $10 to refill the cartridge.
So I changed it to HP LaserJet 3055 and it works great.
The interface is not as good as Brother (takes about 8-10 seconds to send network fax instead of 2 seconds with Brother),but quality of printing is much better, no additional drums to buy, and cartridges are easy to replace and refill, so it is more cost-effective.
HP LaserJet 3055