SSD makes more sense.
However I'd strongly suggest to save a little more and max it out. Future proofing is not a bad idea, plus this way you will not have any regrets whatsoever.
That is mainly what I will use it for during travel. It will not be my daily. I have a 11" 2011 w/ the Sandy Bridge i7 that I am passing down.I don't use it for many processor-intensive tasks... so my decision was pretty easy. I use it mostly for surfing, email, iTunes, Office, and Calibre.
I love the 11" MBA!
If you have to ask you probably don't need either one