There are times when the reliability of the 3-series over the last 15 years or so has been questioned. I would not know whether this is particular models or at/after a certain age.

All the marketing seems to try and differentiate on image rather than price, with Audi going for the maximum comfort, Mercs for history and class, and Beemers for driving. I may nor be alone in advising you to toss a coin, or follow your hunches at the shwroom!

Couldn't claim to be an actual user other than having driven examples of all three current models.

For a view, the Audi might be considered to be the most comfortable, great interior quality etc. However it might also be the least involving to drive. They still feel, to me anyway, a bit nose heavy and understeery on fast A roads.

The BMW is different. It always feels really planted and somehow in touch with the road but might be the least comfortable ( of a very comfortable trio to be fair ! ) maybe not least due to the harsh ride afforded by the run-flats.

The Mercedes would possibly be my choice from your shortlist. I have only driven a petrol C class but it was both pleasing in dynamic terms and well appointed inside. Plenty of seating room front and rear too in my opinion.

So for a vote, I'd go with the Merc, but I'm sure none of them would particularly disappoint. All very good cars. Nice dilemma to have really !

Not to state the obvious but it might be good to at least go and have a sit in all of them before you decide. Sometimes things just feel right, or indeed wrong on the day.

For example ,the skoda superb has the best rear leg room out of any conventional saloon car.

And looks only a mother could love, i couldn't really its just too ugly for words. Why should the Skoda be any more reliable than an Audi badged version, its just another VW but the ugly sister in a charity shop frock.

What reputation for unreliability does the latest C Class have?

Just a thought, which you may well have already had of course, is that all of the above are saloons. Well, at least that's one of their configurations. If you're going to be using the car for family purposes it might be a good idea to consider the estate versions. Maybe you already are? They'd all be good at that too and I'd think, though it's nothing more than a feeling or impression, so please don't take my word for it, but I'd suspect the estates might hold their values better for when you come to sell on.