A tricky one - some of the kitchen stuff IS a bit rubbish in an SE - we've only used the sink to wash up a few times and generally it's just a source of water for filling the kettle or brushing teeth.
The hob is clearly quite limited in usefulness but we find we can cook most things on it.
The bench seat in an SE really is rather small and strictly two seats only - we do find that a bit annoying sometimes although we only have two young kids.
Our "big" holidays have been a week in Mull and five weeks in Europe.
Mull was often cold and windy so we used to kitchen bits a lot (the fridge is brilliant IMO) but in Europe where it was warm, we used a cheap Sunncamp two ring camping stove perched on a table 99% of the time for cooking, water heating, etc - on both trips we used campsite wash facilities for all washing up. We only use the sink for the odd rinse out of mugs, etc.
So the kitchen stuff is nice to have but you do limit space and if abroad in warm weather, it doesn't get used much - but in cold camping, filling up the kettle and have a brew in the comfort of your van (from bed too!) is really rather cosy.