Where were these i3's driven?
I'll also confirm, on smooth roads, its like butter, like one of the smoothest rides. Not any worse than a 5 or 7 series. On heavily pitted or roads with potholes, cracks, expansions, etc its pretty harsh. Almost feels like something's going to break.
I've got a BEV, I've found whenever I've got the vehicle loaded with heavy cargo (often), hundreds of pounds worth, (I put so much cargo, that the rear tires only fit two fingers between tire and wheel well. When empty I can fit 4 fingers) it handles so much better in terms of comfort and smoothness regardless of surface condition of roads. Meaning even rattles are minimized.
In fact last time I jumped in and forgot if I was in the 330e or i3. it felt that solid going over crap roads. Obviously you get dinged in energy consumption with more weight in vehicle, but it does make it feel like a much more solid ride. But its just that, most avg premium cars are about 3500ish lbs curb weight, that extra 500 lbs makes a massive difference in rebound and bounces the suspension.
Most recent time I had 420lbs of cat litter in the car (10x 42lbs ). + 2 adults. 60 mile trip, smooth as my 330e, if not smoother.
In regards to rattles , You've gotta take the car apart to really appreciate and then remedy the pitfalls of the structure and assembly. I've gutted a good portion already, And its missing a lot. Driving around with the door panels off. the road noise was insane. Lining the panels in 1/8 inch CCF and putting them back in already made a perceivable difference at highway speed noise intrusion.
panels back off, and Now, the thermoplastic pieces are getting treated with dampening material, already makes an incredible difference when shutting the doors, sounds like a proper bmw thud, like how the rear doors on the i3 shut with that classic bmw thud (reminds me of heavy 7 series doors closing). They'll be supplemented with 1/8 thick layers of CCF and MLV. the nice thing about the i3 doors is that the shape allows plenty of clearance with window so you can actually lay thicker material. If doing it again I'd order 6 or 8mm foam instead of the 4mm that I got.
But I'm going 3 layers of foam, One on the outer skin, one on the plastic inner cover beneath that white insulation material. and the last layer on the inside part of the door panel. I cant imagine any rattles afterwards.
Am I trashing it?, absolutely, but with love, like every other BMW I've owned.
Rondel stands for something, and I fully utilize all the non neutered abilities its got.
Takeaway. This is an amazing piece of engineering. And I'm not impressed with 'stuff'