I almost ordered this yesterday but the more I thought about it, the 1/3 full toner cartridges made this a lot less appealing. So essentially with this deal you get the printer with 1 1/3 worth of toner cartridges. Since there are 4 carteidges you will need to spend roughly $300 more to get the equivalent to 4 full toner cartridges. In reality will you quickly need to buy 4 cartdges for about $450 (more than the cost of the printer). This is still an excellent deal but if I buy one, I intend to use it so I'm going to hold out on a deal on a 550N.
With the 550n you get full cartridges. Newegg has it for $550 with $35 shipping so it's $585. So in my book the 550n is more than $50 cheaper for a printer with more memory, faster ppm, and several other benefits (based on descriptions at newegg).
Keltron: How well does the 550N work with cardstock in a duplexed mode? I've read that the toner doesn't adhere too well on the second side. I would want to print out birthday cards and such so it will need to be able to do a good job on both sides.