The other thing to consider is that depending on the design you have to lift the keg pretty high to get it over the collar on a chest freezer. Based on the way I mounted mine that was a hassle and once in a while I'd accidentally knock open a tap while lifting the keg into place. Not a lot of fun.
Also, you can end up with a lot of condensation in the bottom of a chest freezer. They're simply not designed to deal with condensation, which happens at fridge temps, so you get a pool of liquid that soon goes funky. Some people use desiccants or towels with some luck but for me it was a pretty big hassle. I had to periodically pull out all the kegs and clean things up, which is difficult due to the height of the collar.
All of this convinced me to switch to a front door fridge like this:http://www.katom.com/598-TBB2448GS.html?CID=GoogleBase2
Keep an eye on CraigsList for restaurants that are going out of business. I picked up mine for $500. I don't have to override the temperature settings at all (saving me from using a temp controller and worrying about short cycling a compressor.)