Thanks - I don't mean to hijack the thread but I wanted to respond because your question is one I've asked myself many times.
The BRZ/FRS is special and remarkable in how it makes you feel when you drive it and I assure you I have more miles than almost any auto journalist (7000 including two track days and many miles in the twisties). It is special in ways you didn't even know a car could be but that doesn't make it better, just different. This is why people are gushing over it...myself included but that refreshing and different take on the driving experience isn't superior at all.
When I test drove the BRZ I was really disappointed. I can't imagine any modern day BMW owner feeling different. However, I had an aging BMW Z4 3.0 /SMG that I needed to move away from so I was happy at the thought of a Toyotabaru that had low maintenance and fun. It was a full month and 1000 miles before I fell in love with it. I bought it on a whim out of curiosity when my local dealer had 4 deals fall through the month of release.
Again, you aren't missing out on the "twins" because they are judged on the approach they took to accomplishing what the 135 is already. Not on the pure result.