I say get the 911. You have the opportunity to do it now, while some air cooled 911s are still affordable. Strike while the iron is hot! If it doesn't work out you can always come back to a BRZ - that's the luxury of a car that is still in production.
I made the switch to a Cayman and don't regret it one bit. I thoroughly enjoyed my BRZ and thought it was an attractive automobile. But I very rarely parked her in the garage and then just stood around staring at her. I find myself staring at my Porsche all the time after a drive
Also, that 993 on the first page is gorgeous! The 993 will always be the zenith of 911 hierarchy to me.
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Current: 2023 GRC Circuit Edition, 2012 C63 AMG P31
Past: (2) 2000 MR2 Spyder, 2017 GTI Sport, 2006 Porsche Cayman S, Supercharged 2013 BRZ-L, 2007 Honda S2000, 1992 Integra GS-R