One thing to consider, once you have all-but decided which one to go for, look for a forum for owners of that model, and ask whether the screen gets marked by the keys.
I have had 3 laptops, all of which had nice screens, but, after a while the keyboard buttons marked two of the screens.
It would get quite off-putting for your customers possibly if the screen is marked like this.
Another possibility, if you can stretch to it, and it is suitable for your application (I don't get whether this is studio work or on-the-road/show/exhibition), is to get a cheap laptop, with a semi-decent graphics card, and a separate larger monitor. A 19" monitor would give a bit more wow-factor possibly than a 14" laptop screen. Whilst you are shooting/away from the computer, you could set it up for a slideshow and grab people's attention.