I've been using Acad LT 2011 since it came out. Using it on 2 computers, a laptop & desktop.
Just installed the 2014 demo on the desktop (I built it, fast CPU, 32GB RAM, Win8 64).
2014 seems snappier. On 2011 drawing a line or getting a distance it would seem to sort of "hunt" for where it thought I was leading it with the mouse. On 2014 it is smooth & tight.
Zooming, copying large complex objects seems smoother & faster.
On Windows 8 the menu bar & ribbon kept getting confused when I would flip from one file to another. On Win7 64 it had no such problem. One 2014 (on Win8 64) it just flips from file to file, no menu bar or ribbon confusion. So far I like it. No flickering issues, even with multiple files loaded.
Regen & save seems about the same. Save might be a tad slower, not sure.
I exported my configuration, and it imported to 2014 just fine.
Next I'll try in on my Dell Win 7 64 laptop.
GChapp