Did you post this same question on Yahoo answers. LoL
I know quite a lot about Laptops and personally i wouldn't choose any of the two; only because i think you can get better for the same money or less.
However; if them two are your only choices then i would definitely go for the Toshiba L300, as although the Advent probably has better specs, the Toshiba however, is a lot more reliable. Which in my opinion is the most important quality when buying a Laptop, as a lot tends to go wrong with Laptops and they don't tend to last long either, if not treated well.
So go for the Toshiba L300.

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