I use a Hauppauge PVR at home and really enjoy it. For the past two weeks I've been using a Gefen HD PVR at work for some stuff, and must say it's quite better than the Hauppauge.
I'm not sure of the price differences. I really like the Gefen due to it's great interface along with the remote control for one touch recording. The Gefen also has internal memory so there is no need to connect it to a PC while recording. Simply
copy it to an SD card when you're ready and load that up on your PC.
The Blackmagic Intensity series of capture devices are also a great choice and can be bought for about the price of an HD PVR. The only downside to them is that your computer needs to meet strict requirements to use them correctly.