Its all a matter of personal preference but Id much rather have a bigger screen. Thatll make for a much better overall gaming experience, be more engrossing and just all around better. 27" screens have taken a nose dive in price this last year.
[URL="http://www.ebuyer.com/390683-asus-ve278n-27-led-lcd-dvi-monitor-ve278n"]Here is an Asus 27" LED[/URL] for £208 that Id take in a second over a 24" IPS.
If at all possible, it wouldnt be a bad idea to get out and go look at some monitors actually set up and running. IPS does have the best color but TN is plenty fine for gaming and watching videos if you have a quality one. My HP is a TN panel and it looks great but my last Acer 22" didnt.
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