I'm selling my Dinan Dinantronics Elite V2 piggyback because I couldn't wait anymore and went with a downpipe and BM3 combo on my 230. It's for the B46 and was installed by Thompson BMW's performance group in Fall of '20. It was on the car for approximately 6 months and is in great condition.
If you want a performance increase that is super smooth, and maximizes your reliability while remaining dealer/warranty friendly, this is the way to go. Really couldn't even tell you had a piggyback on (besides the power increase). That's how smooth it was.
I paid around 1.5k for the system and the dealer install, so I think this is a pretty good deal. Let me know if any questions.