From the Article Dre posted and Shawn quoted:
Some of these details you might already know, but they bear repeating: First, the BRZ has the lowest center of gravity (18.1 inches from the tarmac) and best polar moment of inertia of any car you choose to compare – even a fully optioned Porsche Cayman S or Ferrari 458 Italia.
For me this sums up the appeal. You can fix any car's hp with a few engine mods, or change up the suspension to make it handle better, but to sink the engine several inches lower in the engine bay to get such a great center of gravity you'd have to spend a ridiculous amount of money. I have no problem comparing this car to the MRS, I think it would blow the doors off it. And look better, and have more room. And not have the pre-cat issues. I think they spent the money in the right place: The chassis. And they made the ECU easy to tune so if you decide it needs more power, it should be easy to do. My B13 would get its ass handed to it in many straight-line races (DE with bolt-ons), but when someone on a straight road guns it trying to get me to race, I just shake my head. That's not how I built this car and I don't care about straight-line speed. I have my fun in the twisties and my B13 works great there. Just like the FR-S will, but better than my B13.
FWIW, I bet Jeremy of TGUK throws tons of accolades towards this car when he tests it.