I have an opportunity to buy a used LCD monitor for my Mac. It was a high-end unit, but it's a little old. Most specs are on par with decent new ones. (It's a TFT with 24-bit color, 250 nit brightness, 600: contrast, decent viewing angles and higher resolution than most of its size) but the response time is 25 milliseconds. Will that be a problem? I generally don't play computer games, but I'd at least want to be able to watch normal DVDs and other video (maybe not action movies) on it.
I don't want to say the exact make & model because I don't want anyone else searching for it if it's as good a deal as it looks like. It's a name brand in monitors, and it's from their top line of "pro-level" monitors. It was introduced in 2001. It's going for about $100. It's a 21". As far as I can tell, it originally cost over $2,000. There actually are few stores that claim to still sell it new, but those might just be places that neglected to take the listing down. Those prices range from $1500 to about $2,000.
Personally, i wouldn't pay $100 for it since i could get a monitor with a lower response time (5-8ms) and a higher contrast ratio for about $30-$40 extra. Considering $100 is cheap for a monitor, you might see some heavy ghosting during video playback. Also when changing you refresh rate in your Display Settings, the highest you'll be able to go to is 60 Hertz. Boy is that gonna hurt your eyes. Take what i wrote into consideration and also check this out it might interest you: Newegg.com - $100 - $200, LCD Monitors, Monitors, Computer Hardware
Contrast ratios are tricky and in many cases say nothing about monitor quality. Watching DVDs on it will be just fine. a 25ms difference is incredibly small when dealing with audio to video, most people would not ever notice the delay. Ghosting... well, I'm not sure, if you say the monitor cost $2000 in 2001 it means it's an average/high end monitor so it might not be an issue... just remember that 17" screens cost you $500+ back then. Overall, if you can't find something terrific on newegg for a price that's not too much higher than $100 you can consider the used monitor a good deal, it's totally up to you though.