Which modification is the most reliable and trouble free?

What is your question?

I have a 2017 F30 340i RWD, with MPPSK, VRSF charge pipe and downpipe with Dinan springs. I have enjoyed the car for 5 years and have not had any issues with my car. All my mods were completed at the dealership. Same with all services. My question is on further modification. I am stuck between a flash (MHD) or piggyback (Race Chip) I have heard good and bad about both on Bimmerpost and wanted your thoughts on this matter. I am seeking 425 hp / 460 lb.-ft. in torque. I do not want to sacrifice reliability for this type upgrade. What would you recommend aside from not modding the vehicle?

What makes this problem better or worse?

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How long has your 2017 BMW 340i had this problem?

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