FWIW, I was skimming the i3 FB group and going back about 5 days, excluding any issues w/tires or minor issues, I noticed these:
3/23/18 https://www.facebook.com/groups/BMWi3/permalink/1886760054731180/ - numerous issues he's taking his REx for, unknown year
3/23/18 https://www.facebook.com/groups/BMWi3/permalink/1885976301476222/ - basically a horror story when to comes to his REx engine
3/22/18 https://www.facebook.com/groups/BMWi3/permalink/1885554398185079/ - same as 1st guy, one prob is some problem releasing his fuel filler door. Has to emergency release, which triggers a warning light.
3/7/18 https://www.facebook.com/groups/BMWi3/permalink/1862988827108303/ - looks like he's facing massive repair costs and a day ago, the car's still in the shop w/no news
3/19/18 https://www.facebook.com/groups/BMWi3/permalink/1880680662005786/ - he's posting about something else but I notice his check engine light is on
3/21/18 https://www.facebook.com/groups/BMWi3/permalink/1883620875045098/ - check engine light
There was one other post where I accidentally clicked the wrong link, so I don't know what the issue was. As I said, OP, join https://www.facebook.com/groups/BMWi3/ and hang out there for awhile, watching the posts.