I also watch a lot of TV and this was my major concern as well. Like you, I previously had a Sony 25" TV. Did a lot of asking here in PinoyDVD. A couple of members (switi and SpaceMan Spiff) recommended the Philis 32PF7321. Switi in particular had the Samsung S71 and knew someone who had the Sony V200. He said cable TV quality was not that good on the Samung and Sony. With these recommendations, I decided to buy the Philips.
Unlike a lot of people here, I'm on Destiny Cable. The quality depends on the channel. Among the local channels, GMA is the clearest. On cable channels - ETC, HBO, CNN are also clear. Other channels such as PBO (Pinoy Box Office) were not that clear - I noticed that interlace lines (but then again, that channel was not that good on my standard TV as well). What was a real surprise for me was the Cartoon Channel. I noticed a lot of aliasing (jagged lines). The other cartoon channels (Disney) looked fine.
Again this may be because of my cable connection. I have mine "shared" (hehehe) with a couple of other TVs so signal may be degraded. I might consider getting that booster thing.
To summarize, I don't find it as good as using a standard CRT TV but it's good enough for me.