Laptop for school/graohic design, pref under $500

[Princesstech]

hi
I am looking for a laptop for school and graphic design. It must have at least Four hours battery life. I have Adobe creative suite which I want to transfer from my desktop to the laptop. I also run scrivener and use a lot of tabs in chrome.
It needs to have a nice keyboard with no lag, as I need to use it to write exams (when every second counts).
Also, the sturdier/hardier/durable the better, it may get be bumped around a bit
I am looking for something under $500.
I live in South Africa, so hopefully something available here. (Otherwise I have relatives in the US to whom I can ship it to and they can send it here.).
even if you can't name a specific model for me (although that would be preferred), can you guide me with the following questioms

• 
  What is the difference between i7 and i5? Is i5 good enough for my graphic design purposes?
  What is eith the U? I need battery life for school, but how much would it impede the speed?
  What brands offer better quality
  • 
    

That's it for now

 

[hang-the-9]

For $500 you will limited with capability to run Adobe CS well. I doubt you can find a new laptop with a Core i7 CPU for $500. i5 is a good CPU, so if you find something locally then you should be fine, just keep in mind that you will have something you need to give up, maybe RAM, drive space, video card speed, etc... for the price.

The U is probably a low voltage designation, depending on what you are talking about.

ASUS and Lenovo were the top two brands for quality in the last survey I look at which is probably a year or more old by now.