Who has one? What do you think? How does it work?

Main question: They say you can record 1 show while watching another. With the dual tuners is it possible to record 2 shows simultaneously? I know this would probably be a strain on the hard drive, IDE bus, PCI bus...is it possible?

Even if I need seperate drives on seperate channels? Just wondering...

Simple math, two tuners, two recordings. In MythTV even when you're watching "live" TV you're really watching a recording (how else do you think the ability to pause, rewind, ... live TV work). Just so long as you've got working DMA for you HD there is more than enough bandwidth for two SDTV recordings. I've done the math elsewhere in the forums if you're interested in the details. We've got people around here using low spec machines as backends with 2 SDTV PVR cards and an HDTV card without major issues.

Playback is another story, as decoding an MPEG stream is relatively CPU intensive and there are realtime "hard deadlines" which must be met to achieve smooth playback.

I have a pvr-500. It works great (along with my pvr-350). I can record three shows and watch a recording at the same time. But I use the hardware decoding of the pvr-350. So my CPU is never really taxed to much. I use an sata harddrive. I don't think it is particularly fast. It was on sale on newegg.com