Well, as you pointed out, they have the same resolution....so it is pretty much strictly a matter of preference. Is the extra size worth losing the specs. As we all know, the most important think for a gaming monitor is refresh rate. I had a viewsonic gaming monitor...a vx924 with a 2ms response time. It was good for gaming, but then I got a larger Acer 22" monitor with a 5ms response time. I am a heavy gamer, counterstrike, crysis, etc. etc. and I can honestly say that the difference between a 2 and a 5ms response time isn't noticable. Furthermore, the extra contrast ratio on the acer made the picture look more vibrant and detailed to me, instead of washed out.
So here is my summary:
Any refresh rate under 5ms should be good.
Highest contrast ratio possible effects the quality of the whole image.
Resolution is the same so it is up to you, I would go with the 24" with better specs, because quality is more important than size (to me).
In general, it's probably user preference whether a larger screen or small pixel pitch is more important. Up close on a desk, I would prefer the 24".
I did have the 28" Hanns G on my list but decided against it for lack of inputs and the fact I'd rarely use it further than arms reach anyway. Looked at the Dell 2408WFP and Gateway FHD2400 too, but ended up grabbing the BenQ G2400WD for $360ish shipped. No complaints at all...and I'd highly recommend it for gaming. http://www.newegg.com/Product/Product.aspx?Item=N82E168...
it all depends on how you see things. i always choose quality of quantity, but some people prefer it the other way around. if you really need to have such a large screen, then get it. but if you care more about image quality, get the 24".
well usually the the faster the response time the better when it comes to gaming. especially in fast moving scenes. less ghosting and distortion.
this is my experience with this:
my 19" monitor has a 2ms response time, then i tried to replace it with a 32" HDTV i had lying around doing nothing. thing is, the HDTV had a slow response time of 12ms.
i decided to go back to my 19" monitor. why? when gaming, the HDTV was actually displaying frames very slowly. ummm how do i explain this....it was like seeing the game run at 12FPS when the graphics were actually running at 80-100FPS, weird.
obviously, i never had this had this problem with my 19". i had to put on vertical sync to get the 32" to work properly but that was sevierly limiting my system and even then, there was a lot of ghosting.
I would take the 24" monitor over a 28". The 24" would take less power from the graphics cards to run decent FPS, would take up less space on the desk, and of course, the better response time is easier on the eyes when gaming. But that's my opinion. You have to make up your own mind as to what's most important.
Just keep in mind, the best panels as far as color accuracy, will not be the best gaming panels. For instance, the Dell I mentioned is an S-PVA panel and has excellent color accuracy. But these panels suffer from input lag that competitive gamers would not desire. The TN panels have worse color accuracy, but don't suffer from input lag making them nice for gaming. They are also less expensive. See this review for more info: http://www.anandtech.com/displays/showdoc.aspx?i=3302&p...