One of the new coding changes I took advantage of when introduced by Code My Car (whom I'd recommend), is that the interior warning sound effects (what some call "bongs and glongs") can be changed in the i3, from the rather insipid non-BMW sounding "bionks" that we now get, to either standard BMW warning "glongs" , Mini Cooper, or (what I think is neat), BMW owned Rolls-Royce warning sounds.
I had mine changed from i3 to Rolls-Royce. I figure it's the closest to driving a Royce I'll ever come. As you'd expect, the sounds are quite elegant; they sound like stringed instruments being strummed. I liken the most common "door open" sound to a lute being plucked. I did, however, have the seat belt warning sound disabled. A small and perhaps insignificant change, but one I like.
I also have the folding mirrors, start-up in EcoPro mode, UK navigation voice (why not, got the "Rolls-Royce" thing going on!), Key fob button opens the rear hatch instead of the "frunk", BMW Office enabled, unlock door with car off, taillights as DRL's, AM radio enabled, AC buttons remember last mode, full capacity of the fuel tank, and a bunch more. The latest coding updates that his company offers is dated 10/6/15.
