HTC one X has the best display, GS3 is better in all others
Now the flagship Android phones are Samsung Galaxy S3, and HTC one X. Both use Qualcomm latest S4 dual core CPU and have 720P display. One X has the best display, as good as iPhone 5's and overall feeling on hands, GS3 is better in all other areas, such as
* UI smoothness
* Better picture/video quality.
* Louder/Better voice quality.
* MicroSD slot
* Bigger battery and removable.
* 2GB RAM.
You do see/feel the difference between high quality phones and cheaper/lower quality phones.The major difference mainly in the area of camera, display and reception signal. I don't agree what you said about laptop(no big difference between the cheap and expensive ones). If you pay attention to Apple MacAir/MacPro laptop and other laptops, you do see the big differnece in the display(viewing angle and brightness).
In term of the plan, prepaid is much better deal than those 2 year contract(usualy end with $70-80/month after tax and regulation fee). If you like AT&T network/signal, check out H2O and straighttalk, both use ATT network. H2O has 5c/min prepaid plan if you don't call that much.
If you use data a lot, the best deal is T-Mobile $30 prepaid plan(which include 5GB data and 100 mins talk) at Walmart.
If you prefer Verizon, then check pageplus(5c/min prepaid) and other flat rate plan.
All prepaid plans don't have extra charges(such as sales tax and whatever stupid fees).