Depends on where you're sitting. The area directly under the opening is about the same, but the rest of the roof liner is thicker, leaving less room https://www.bmwusa.com/content/dam/bmwusa/BMWi/i3/2019/overview/BMW-MY19-iModels-I3-Overview-Conscious-Design-03.jpg.bmwimg.xlarge.jpg
If you're tall and sitting further back, your head might hit the back edge of the opening. If you wanted to lean over to get to the glove box, or open the other door, it could be an issue...depends. It's one of those things you really want to check out yourself so there are no surprises afterwards, should you decide to buy one without trying it first.
