Well I have a 4 door Aygo sitting on my driveway at present (its a relatives) and the rear door seals are dripping as we speak.
"It's a known fault", yet is totally unheard of on 107s?
I am going to sort them tomorrow as I did with my C1, by smearing the seals with silicon grease, as well as the one in the engine bay, to stop rain water getting on the engine block and electrics. I only have to do this every 4 months.
The door seals, engine bonnet seals leaking are a well known fault on C1 and Aygo (I do not know about 107's), but they are all off the same assembly plant, so i assume there must be some 107's leaking as well.
Anyway, according to my local citroen dealer in the knowledge, the fault seems to have stemmed from the way the seals are installed at the factory, by thumping them on with a mallet (I kid you not).
This it seems, reduces the pressurisation of the seal against the metal when closed, hence drips especially when in a downpour.
I have been told that all car seals from 08 onwards are now hand installed only, so the seal seems about 2 to 3mm thicker (I have witnessed that on 08 cars in the showroom) but do they work better, who knows ?
Anyway my silicon grease method works as a solution, and thats now two years on, so I will live with it.
Silicon grease details...
RS components tube of grease part ... 494-124
or buy from any plumbers merchants.
(Never use vasaline as that rots rubber)