Budget tablets with decent battery life?

[Lairewen]

I've never had a tablet before, but I'm looking to buy a lower-end one in the near future. I don't need much from it - web browsing, ebook reader and maybe a media player. But battery life is a big deal. I've seen ones that advertise up to 12 hours web browsing, but is this actually realistic, or should I lower my expectations with a budget of just

 

[jev]

Advent Vega, 10.1" for