I'd be curious to know where you can pick up 100 OTA channels in one geographic area that you can actually receive and see on a TV screen. I'm located between Baltimore and D.C. and I get about 51 channels when I run a scan, many of which I can't actually receive. In reality, I can actually receive about 30-40 channels, and most of them are sub-channels. I get duplicates of all of the major network channels from each market, a couple of independent channels, and 4 or 5 PBS channels, all in HD.
I echo the sentiment regarding Tivo's guide data. I can't recall any instances where it was wrong unless there was a last minute schedule change that occurred too late for Tivo to update it.