Got my cable card set up on my Series 3 (HD) and it wasn't too bad.
Moved into a place that has Comcast as part of the rent but you need to set up an account. Called and they wanted to send me a SD box (hell no) so I went to the local (10 miles away) office got the card. They even gave me a sheet with the right number for cable card authorizations. Got home and redid setup on the HD (since I went from Antenna to cable). Called in and they couldn't get the authorization to work. Tried twice. UGH!
Went back to office (wasn't waiting for a tech) and swapped out card. Old one was Scientific Atlanta (yet Tivo says Cisco on screen). New one was Cisco and did firmware update. Called in and within 5 minutes I had TV
Gonna be weird to go from 4 tuners (OTA Roamio) to 2 tuners (HD). But I should be fine.
I had heard horror stories about getting cable cards going but this one really wasnt that bad other than the 1st card being a dud. My only issue was the 2 people I spoke to with the 1st card Spanish was their 1st language (I could hear Spanish being spoken in background) so there was a slight communication gap (not as bad as the India ones)
3rd person was awesome.
So far so good