You will always pay a "bit" more from a Ford dealer

There are different versions of the 2.0L diesel, at different power levels, the 163Hp is "peaky"("gutless" at low revs) and needs to be redlined through the gears to get the performance, especially off the line/ at low speeds, it has a narrow power/ torque band and has very little power below 2k, and above 4k, Ford offered a software update, but a bluefin/ remap/ digital tuning box helps "fix" it the 140Hp may appear to have less power "on paper" but is more tractable/ quicker on the road in more situations than the 163 due to the wider spread of power/ torque

There are 2 different types od 2.2 (diesel) the earlier 172Hp (which was replaced by the 163 2.0L in the lineup) and the 200ps 2.2

The 2.2L is quite a bit more powerful than one of the 2.0 and you can remap the 200ps to 220Hp (psa engine)

There is a petrol turbo with the same 225Hp 5cylinder 2.5L (Volvo) engine as the Focus ST - this is quick but a proper gas- guzzler (can be modified to 300+Hp, just like the Focus)

Its a big, fairly heavy car and the 1.8 is a bit small for it, i would avoid the 2.0L 163Hp (for the reasons above) and recommend the 2.0L 140Hp or the 2.2s

Any reference to 2.0L or 2.2L mk4s/ "mk4.5s" - make sure you know WHICH 2.0L or 2.2L