I have drive all 3. I basically eliminated the 335id for the reasons you stated.
The CPO is really tempting. My only real concern is getting stuck with a car that has higher miles that I owe money on. A buddy of mine is in that boat with an 06. Great car, but out of warranty and he is having issues.
As far as the drive, the M was just amazing. There is no comparison. And, being a bit of an enthusiast, I start to think with the smile on mg face and I forget about practical aspects.
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