Well, I ended up buying one.
Recording works well, but the playback feature is a bit weird. Sometimes the software says it is playing a video clip but nothing appears in the playback window. If you double click on the playback window a couple times, it works. I will be calling EZWatch tech support soon on that one.
One other problem was the 4 video inputs on the card were marked backwards - Channel 1 was actually channel 4 and so on. I thought the card was dead until I started moving connectors around on the card.
I bought EZWatch because the HP PC I wanted to use has a Via chipset - something the Geo card makers said was not compatible with their hardware and software.
EZWatch has no restrictions on BIOS or the motherboard chipset. You just need a reasonably fast CPU, lots of RAM and a big hard disk drive - same as all the other DVR boards.
I don't usually buy pre-built PCs but this one was a factory refurb and cheaper than what it would cost me to build one from scratch.