These are basically the same device, so you may as well get the least expensive one. If you have been thinking about getting a power conditioner, some have triggered receptacles. I don't know how you feel about conditioners, so how you do this is up to you but I like clean power, so that's how I would address it. $65 is about the least I have seen these at retail, though.
Here's Russound single outlet:
http://www.avereststore.com/servlet/the-27857/110VAC,12VDC-Triggered-Outlet/Detail
You could probably make one with a 12VDC or 24VDC relay, a 12VDC or 24VDC transformer, a project box and a short replacement power cord. Wouldn't be as small, though.