Cool. But I had to think about it.
It almost screeched into uncool because Peugeot has ruined the front of the car with its stupid corporate grille after making such a good job on the back. Incidentally, this is also why the car misses Sub-Z by a fair way. If they'd made it pretty at the front like an old 406 Coupe, it'd be Sub-Zero.
Everything else though is cool.
- It's a French coupe, so it's a little alternative and quirky rather than ostentatious and brash like a German coupe (ironically, main rival Audi TT excepted, which is neither ostentatious nor brash. Though it is an Audi...)
- That rear window, and the St Louis Gateway Arch-style metal roofline, are two of the coolest (and least contrived) details to appear on any car since the chrome fluted indicators on the Citroen DS.
- Contrary to what others have said, all the engines offer enough performance, if you consider what European (where the car will mainly be sold) roads are like. And "enough" is always better than "lots", because you can always enjoy "enough" but "lots" leaves you wishing for more space in which to exploit it, and therefore frustrated. Being frustrated that you can't use your car as God intended isn't cool.
- It stands out. A lot. As Jondot said, it's particularly imposing - the sort of car that grabs attention. There's a Ferrari California going around where I live and it's significantly less of an attention-grabber than an RC-Z. Out-Ferrariing a Ferrari at making people take notice (especially at a fraction of the price) is cool.
Incidentally, I'm also going to go with Stotty's proviso: When it becomes ubiquitous, it loses its cool status.