5 hours is not enough....
90min on the train to work
1 hour lunch
Check emails now and again (like i check phone for texts)
90min on the train back.
That's 4 hours plus the standby time and checking emails...its too close. If I so much as go somewhere to eat by myself, thats a flat battery on the way home.
Full OS on Tablet = dead battery.
11.6" that sounds too big really. I think the iPad is the best size. a 7" would be too small imo as it would be in the middle of the iPhone and current iPad to much.
With this size iPad I can hold it in portrait on either side and type fine like a phone which is handy! And its not like its uncomfortable.
 
	