definitely izzy! To me, izzy looks much better than meredith. Each is beautiful in their own way but as for looks I think izzy stands out more. Besides, meredith's hair seems to be always frizzy and in a mess. Lol :P
I guess I have to go with Izzy even though I'm usually a brunnette kind of guy. Meredith only occasionaly looks pretty to me while Izzy usually does. There is just something a little off about Meredith's face.