The small door really is not that bad for most people.
I'm 6'4" and have no problem getting in and out of the campers all day.
I can't say I have ever hit my head on it?
But I really lean forward when getting in the camper to make sure I don't bump.
Coming out of the door backwards really helps for an easier exit.
We do have people that visit our showroom and come to the trade shows that do bump their head from time to time.
You can even caution them ... "be a little careful when you get in the camper, the door might be a little smaller than you are used to"
They look at the top of the door and start to go in and they still manage to bump their head somehow?
With the right camper steps and a little practice, it seems to be just fine.
Having the small door makes for a STRONGER camper frame on that rear camper wall.
For strength and durability I would take the small door every time.
I had a friend with a 1986 Starcraft pop-up truck camper and it had the double (full sized) rear camper door.
It worked OK, just took a little playing with to get it set up.
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