Interesting debate, this one..I went to buy a pure tech petrol, of some sort, and quickly found out that there wasn`t any in the UK (certainly so for the C4 hatch). Certainly the dealer didn`t have any on the demo fleet and when I asked about build and delivery, dates were very vague. I did a test drive on a diesel and the salesman did say that the acceleration on the petrol was quicker than the diesel (and thats quick enough)..I dont do much mileage and quite a lot of `short hauls` but the deal on the diesel I bought was too good to miss..
As a point of debate I suppose, I asked one of the technicians about this latter point and he said that long distances at motorway speeds in 5th gear don`t do anything for the DPF regeneration, similar in fact to stop start round town..The only way to sort it is 3rd gear, at 50mph (3000 revs) for about 15 mins a month at a constant speed..Engine sounds awful but it does regen the DPF and off you go..Oh yes and he did say DONT use supermarket fuel because it has insufficent cleaning agents that these engines need.