Great used car for a DIYer
The price of many BMW's drops to 50% of the new cost when they go out of warrantee, even when they have low (30k) miles, including the 335xi. I also like that 1) it has 300 hp and 300+ ftlbs of torque, 2) is available with a true manual transmission, AWD, and 4 doors (I have a family), 3) they are not as rare as a Golf R, and 4) they are usually well cared for and not beaten like a WRX STI owned by some kid. These traits/combinations are hard to find in most cars.
I don't like the electric water pump. Depending on the age (and not necessarily mileage), they fail. I replace mine (myself) for $600 with only 36k on the odometer, but it will cost $1000 to $1500 to have someone do it for you. Also, small potholes feel like craters when driving the car.