I highly recommend Brother. We have a HL-5140 USB printer here at work and it has never let us down, never paperjammed, toner lasts for ages, good build quality and solid (Windows) drivers. All that and its not particularly expensive.

My cousins actually have a pair of low end Brother printers on their electrical trade counter and they put some serious mileage on them printing Invoices and Delivery Notes. Again they prove to be reliable and low cost.

They are all USB printers though, no real experience with the network ones.