Question about processing power of Win8 tablets

I am currently rocking a 3 year old Dell XPS 13 with a 2.66GHz Core 2 duo, NVIDIA GeForce 9500M, 8gb ram, and an ssd but I'd like to get a windows 8 tablet as my main computer (if I can manage on my postdoc salary!). My question is whether I will see better performance with a ULV Core i3 or i5 and intel graphics than with my current computer. I mostly use my PC for internet, writing papers, a little photoshop and MATLAB. Thanks!