ENGINE PREFERENCE
I have been very pleased with the N55 engine in my X3. It is powerful and smooth in operation thanks in part to the I6 configuration. The F-Pace uses a Ford-derived supercharged V6 (or a diesel engine which I would not consider). Jaguar has plans to introduce its own turbocharged I6 engine in the next year or so. The X3 35i is within a half-second of the F-Pace 0 to 60 mph and gets 10+% better fuel economy on the highway. The X3 35i is a good trade-off for my driving preferences.
http://www.motorauthority.com/news/1...n-2017--report
RELIABILITY
The X3 35i in the F25 version has been around long enough for most of the bugs to be addressed. The Jaguar F-Pace is a new model from a brand that historically has not been the most reliable. Early reports from F-Pace owners suggest some widespread problems. Consumer Reports rates reliability of the X3 as average and the F-Pace as worse than average.
RANGE
The X3 35i is more fuel efficient and has a larger fuel tank giving it about 20% greater range than the gasoline fueled F-Pace. I often take 700 mile trips and like the convenience of only having to stop for fuel once in the X3 while maintaining a 100 mile reserve. I would experience significant range anxiety in the F-Pace on such trips.
SIZE
I have a narrow parking spot in an underground garage with a concrete pillar on one side and a permanently parked classic Porsche on the other side and a tight turn for entry. My X3 with surround view is easy to maneuver in these tight quarters. The F-Pace is about 6 inches wider and 3 inches longer than the X3 and would be a challenge to park in my garage space.