I actually wanted to have a go in the ND Mx-5 but they didn't have one...So I gave the spider a go instead. I'd probably go with the MX-5 for budget reasons, should be very very similar drives though.
I'm just agonising on whether I can live with one day to day. MX-5's have never been practical cars, but the ND doesn't even have a glove box.
I'm weighing up the practicality and how often I'd actually drop the roof when 95% of my driving is a commute through the city centre at rush hour. My heart says MX-5, my head says boring, sensible hatchback.