I&#x27;d go with the 15&quot;, which is similar to the model I&#x27;m typing this on. The 2.2 GHz quad-core i7 is plenty fast, and the extra cores will often provide a speedup. You&#x27;ll also get a discrete GPU, which is worthwhile.<p>The size and portability of the 15&quot; is fine as far as I&#x27;m concerned - I doubt there&#x27;s a practical difference really. Certainly it will fit fine even on a small desk.