The Dell is a bit more expensive but really - is it? What you might find in favour of the Dell is the colour accuracy that is supposedly pre-calibrated at the factory, a much larger amount of ports and if I remember correctly, it can swivel. The type and number of ports in itself might be the equivalent to buying a usb micro bus (run multiple USB devices).
The Acer is no slouch and given the screen are pretty much from the same origins, then its really if you want the superior colour control and additional bells and whistles. For simple gaming, either works and for centralized ports and accuracy the Dell is a better deal (though more expensive).
While the above is based on specs, it really comes down to what you need, your budget, your aesthetics etc. Personally, I would go for the Dell and of course, immediately make sure I read the "allowance" if any, of dead pixels. I am a bit OCD about having zero dead pixels and you need to make sure your purchase meets your expectations.
