In reply to Blue Straggler:
The 90 bhp has a waste gate turbo, whereas the 110 has a variable vane. As a general rule, the variable vane turbo tends to be more troublesome over a long period of time as the variable bit tends to stick with soot and old oil from the EGR valve. This will tend to make it over or under boost, and go into limp mode.
I think it's only the turbo and the tuning that are different between the 2 engines.
What I would say, is the PSA revamped the very very troublesome 1.6 DV6 engine around 2009 / 2010, to a much more robust and reliable unit - also called the DV6. The difference is the troublesome one has the injectors very prominently displayed at the front of the engine. These are the ones to avoid. (You may need to remove the engine cover to see). The more robust engine it's much more difficult to see the injectors, and they are mounted at the back of the unit.