Cross shopping an X3 and a Type R is a bit odd.
You mentioned being impulsive. You may want to sit down and unimpulsively make a list of what characteristics you want in a vehicle.
How important to you are:
- Ultimate handling?
- Ultimate acceleration?
- Comfort?
- Gas mileage?
- AWD?
- Winter driving capability?
- Repair costs?
- Front passenger comfort?
- Rear passengers comfort?
- Baby seat accessibility?
- Cargo capacity?
- Towing (if your X3 is so equipped)?
- Manual vs. automatic transmission?
- Predicted reliability?
- Etc.
I don’t know what kind of driving you do, but I’m getting 30+ MPG on the highway in my M40i (in Comfort or Eco Pro modes), which is higher than I expected. Even my city driving mileage isn’t too bad.
If you’re worried about repair or maintenance costs, you can buy plans from BMW.
If you want better fuel economy, there are better choices than a Type R.
I’m also trying to picture a Type R as a daily driver.
If you really just want another shiny toy, then do what you want to do.
Don’t forget to factor taxes into your calculations.
Re collectibility: I wonder what will happen to ICE collectible car prices when EV (or whatever comes next) eventually supplants ICE. But I also agree with the commenter that if you really want a Type R to be a collectible, don’t drive it.