OMG!! I cannot believe this!!

It seemed smaller than that when I tried it on in the shop (although I actually tried the ink one on, not the leopard). I am 5'1" and size 10, so similar(ish) to you bag*mad and IWantANewBag, but there is no way I am as slim as you two! I reckon my 9" laptop might fit in that - have just looked at the sizes on the Mulberry site, and will take it with me tomorrow to see.
 
Mirrors can be deceptive, camera usually more accurate I think. You are right, the regular must look a very similar size on you as it does on me and bag mad bag. In fact it will look bigger on you than on me as I am 5ft 9. Good idea to take laptop, then you can be sure you choose best size for you.
 
i expect if you 5'1 and a size 10 then a regular alexa would be fine, the shape changes so much once all the tissue is out and all you bits and bobs are in there! its a very slouch bag, it hangs nice though i think!