for what its worth, I have a Topfield TF5000PVR Masterpiece, and it has worked flawlessly for the past 4/5 years or so.
I decided with more and more HD on tv and some movies only available on HD, combined with the fact that I have a 42" HD screen, it was time to upgrade, so went with the Sony PS3 with the live tv plugin.
Pffft, bloody hopeless, it has twin HD tuners, but will only record on one of them, not both, forever freezes and pixelates or loses the signal when recording too, and the picture wasn't really much/any better to my tired old eyes.
So it was back to the toppy, until it gives up the ghost, it's been bullet-proof so far.