I use a sandy bridge Core-i3 based HTPC, with a Ceton InfiniTV 4 PCI card. I’ve been using this for 3 years, and just recently switch to TWC.
I’ve always love the setup, and it’s already paid for itself twice over, and acts as a central media server for the rest of the house. I agree the tuning adapter sucks, and it has caused me to miss a few recordings… But in general things seem to work fine.