Double or single self inflating mats for the dc

[Maybee]

Thought camping sounded like a lovely idea(err 2 weeks ago when the sun shone!) So I hope to go later this spring and summer. I looked at the self inflating mats and got 1 single for me so far. Should I get another single for ds1 and then a double for ds2 and ds 3 (ages 2 & 4) or just singles for everyone? Doubles are hard to come by it seems. It'll be just me and the kids so I want trips to be as hassle free as possible as I'll need to supervise them and set up at the same time.
Tips anyone?

I bought singles for my 2dc's (6 + 4), as I thought that when they are a bit older and since we often camp with friends, they may want to swap tents which would be a hassle if they were sharing a mat. We bought high gear singles for them and a vango double for me and dh.

Singles for hillbilly's reasons, plus I would think doubles would be more of a challenge to store, transport and roll back up (rolling up a single is a triumph of will around here).

Thanks.
Are Hi gears good then? I must have a google. Lidl have their camping gear in tomorrow so I must have a browse. Any suggestions for user friendly cookers?

I like the Hi Gear because they have raised edges so the kids don't roll off so easily if we are on a slope ;-) and I like Vango for us because with a bit of extra puff the ar 7cm deep (or supposed to be!)