The i5 is way stronger in most tasks, but the A8 has better integrated graphics.
I know that the a10 has r6 graphics which is alright but it has 1.8Ghz and a quad core
The i5 has "Intel HD Integrated graphics" which sucks but it has a dual core with 2.3
For better graphics then the AMD
For mildly better cpu power the intel
But having said the intel is faster you will not notice in day to day tasks like email or web browsing.
You might notice that the AMD is better if you are multitasking.
The extra cores pay off