I just made the leap into HD recording myself and picked up the HDHomeRun. I have to say I love it so far. Extremely easy to set up. For me, it just works. I love that I can have access to it anywhere on my network. Not sure how the setup goes for VMC, but everything went very smoothly with SageTV.
You can check out the instructions for VMC here...http://www.silicondust.com/hdhomerun..._mce2005_vista
It's a little pricier than some of the options out there, but it has 2 digital tuners built in and is a bit more versatile than your standard tuner card.
Good luck with whatever you choose.