As a clearly objective observer, I have to say, I like Mazda's take on the styling a lot better. The new Fiat 124 Spider is fully based on the ND Mazda Miata, with Fiat swapping out the body panels and the engine/transmission, basically.
I think the 124 will skew older on buyer age, because it's definitely a more "classic lines" roadster that calls back to the lovely Fiat Spiders of yore. Can't say I'm in love with it, but it doesn't look bad at all. Except for that odd contrasting windshield surround.
And I'd be lying if I said I wasn't jealous of the 1.4 MultiAir Turbo that this car is getting, which is also used in the 500 Abarth. It's a cracking engine, and you know it's going to sound delightful on this car, if a bit less obscenely hilarious in its aggression than it does on the Abarth.
The new Miata for me definitely has more modern, almost concept car-esque styling. It's aggressive. The 124 isn't by any means staid, but it's clearly a retro-modern design, and I've never really been a fan of that automotive trend. I'm quite curious as to how much it'll cost - my guess is "a lot more than a Miata" at least here in the states. I'd wager $35k to start?