The only concern I really have is with gaming. Since it's an IPS panel I should see very minor delays compared to a TN panel, I play a lot of shooters so this may be a slight issue.
Does anyone know the cheapest place to get them or should I just buy direct from dell?
That is called input lag. The dell U2311 IIRC has a pretty low input lag. Lower than a lot of TN panels.
Response time affects ghosting, and frankly... it shouldn't be too visible on any modern IPS monitors.
A great example of this. My secondary TN is a 1080p LG, and it's 2ms. It has tons of ghosting and tons of input lag despite being a TN.