Yep, printer drivers are already available in Windows, which is nice. According to the manual, the 4m uses 195W when printing, and 55W in standby. The 5m is 300/80, and 22W in "power save" mode. I'm guessing that's a mode where the fuser is fully cooled off, so it's probably slow to spool up if you enable that.
You should be able to throw most dialects of PCL and PostScript at those printers and they'll work fine, so this fits the GP's requirements (not having 500mb of software)
Anyone know how to make Windows speak PostScript?