Hi,
We hired one as a family of three, with one ds6 last summer for a week.
I have to say, i found it a bit limiting, ds slept in the pop top and it was a bit of a nightmare having to sleep with one eye open incase he needed the toilet in the middle of the night as he had to climb through the hole and down the seats. One night he dropped out and fell 3 ft, another night i couldn't climb over dh to get the sliding door open (he was sleeping door side) and an accident occured.
You fold out the chair and slide away the table to get the bed out. So at breakfast time, if you want to get the kettle on and crockery out, you have to pack the bed away etc as the sink and cooker surface glass top has to be lifted up and everything moved etc. In our tent we would just stroll out to the living area independantly and let everyone else sleep. I also found the bed very uncomfy a huge seam where the seats fold in half and the seat belt buckles seemed to dig in no matter how you lay.
It was pouring down in Belgium when we got there, and it was a bit small and confining stuck in the tiny camper with DS kicking the table leg out all the time. When you have to cook in the bad weather it is a little dangerous with kids and a wobbly kettle or pan on the gas ring and having to crounch around and move legs to get to the cupboard etc.
If you have an awning up you can't drive around without packing up completely, as you can with a tent or caravan. Not a lot of storage space either, we barely got all our clothes and bedding in the back.
I don't want to be uber negative, but these were the practicalities that we hadn't foreseen.
We enjoyed our holiday, it was a novelty having the van, and believe me we are not fair weather campers. DS loved sitting up front with dad, I got terribly car sick in the back as it seems to swerve more! The plus point was not having to erect a tent in the rain, and it meant you could move very quickly everyday. If I was to buy, i'd be using it for weekend trips, festivals etc only. For long term hols I think I'd look at a caravan or RV type vehicle, or stick to our big fabulous tent.
Why don't you do what we did and hire one for a long weekend to try for size and practicality?