I traded in a 2015 Cooper S Hardtop for the SE, so I actually have a lot of experience with the same exact car with two different propulsion systems. I loved my ICE Hardtop, but the SE is so much better in every way. It accelerates quicker, has less body roll, is silent, has no vibration, and essentially costs nothing to drive. I spend about $40 per month in electricity charging it, as opposed to over $300 per month for gasoline on my 2015 Hardtop (I drive about 500 miles per week). I also just went past 20,000 miles in my SE and have had ZERO oil changes. In an ICE Cooper it'd have been 2-3 oil changes by now.
I will never, ever buy another ICE vehicle.