Look, from what I can tell you should just an m340i it’s sounds like it’s exactly what your looking for. I’m telling you won’t regret getting the m340i over the 330i but the other way around I can’t guarantee you’ll feel the same way. You may have to travel out of state to buy an m340i then drive it home, or just wait until one shows up in your area.
Some 540i come with M sport brakes some do not, if they are not colored I believe the car you’re looking at was not optioned with them.