Input lag is typically higher. However, there are TV's that don't have noticeable input lag when compared to a monitor. Anything below 32 ms of input lag is pretty much lag free (to our eyes/brain). Monitors are mostly overpriced but nobody is complaining, TV's and monitors are 2 different markets. As for picture quality, contrast, color--TV's do win, but it's definitely not just black and white. If you feel you want a 42" TV, then buy one- it's really that simple and mostly preference.
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