Here are some
Alternative TN Monitors for you.
You can get two of them for about the same price as one from Alienware.
Again, I would recommend getting either the cheapest pair of TN panels you can locate or saving a bit more for a pair of IPS/PVA displays.
You are correct in you assumption, a smaller screen with a higher resolution will be very pixel dense and quite detailed from up close.
Even a 24" display with its 1920x1200 resolution, however, is quite detailed from close up...
Do not stress out about having a quick response time.
Your eye will not be able to tell the difference between a 2ms (.002 second), 5ms (.005 second) or even a 16ms (.016 second) response time.
FYI, the 60Hz refresh rate of nearly all LCD displays is equivalent to the screen switching roughly every 17ms (.01666 second).
Also be sure to ignore any Dynamic Contrast Ratio propaganda.
DCR is achieved by sacrificing what little color gamut and fidelity your TN panel has to artificially brighten bright spots and darken dark spots.
The true contrast ratio for a TN panel is usualy in the 500-1000:1 range.