Have done 3 in a tent and 3 in the camper and i am not sure i could go back to the tent now.
In the camper fields you have a lot more space plus the comforts of the van.
And, it gives you some quiet time away from the craziness when needed.
We have always gone in on the Tuesday morning when they open the camper fields and have always got a good spot in one of the fields close to Gate C, maybe a 5 mins walk so can pop back up to camper to top up the beer rucksack if needed.
But, i would not fancy being in one of the fields at the back of the campervan fields as thats got to be an extra 15-20 min walk to get to the entrance gate. May not sound much but after you have spent the day walking/dancing/stumbling for miles around the place i wouldn't want the extra walk. This year i managed to get from the Pyramid Stage to the van, top up the beer supply, and back again in 40-45 mins. I wouldn't want to add an extra 20 mins each way to that if i was in one of the back fields.
So thats my tip, get there as early as you can in the camper as from what i have seen they fill up the campervan fields from front to back e.g. Get there early to get in one of the fields close to the gate. [But, weirdly, we woke up on Friday morning and a T4 had set up camp right next to us overnight]
As for space, well this year we had people camping with us and the stewards had no problem us putting up 3 tents in the space next to the camper. Although only 2 tents in the pics but you get the idea of the space.
And you should deffo try and get tickets. Is an amazing week, it blows my mind everytime i go. Really is something there for all tastes, old and young.