I went for a 163 manual, mostly on cost grounds (it's easy to ratchet up the cost when you start climbing the options list and for me going to an XE at all is stretching the amount of cash I want to spend on any car), but for other reasons too. I reckoned that my current car is the same weight and only 120 bhp, so this would be a useful 1/3 increase on that, plus Jaguar deemed the 'old' 2.2L 163 to be fine in the XF, which is much heavier, and Jaguar aren't known for making badly underpowered cars. I had largely discounted the petrol versions from the start but that may have been an error as it sounds like the 200 and 240 are performing well.
I've driven the 180 in both manual and auto versions. It was pretty clear to me that the 180 auto was a good combination, but then again it should be. Reports coming from 163 owners on here seem generally positive, however, so I remain optimistic that I haven't made a terrible mistake...
Just like choosing a colour, there are no right answers.
I'm not sure there are any really wrong answers either.