Can't speak from direct ownership experience, but we did test drive a new I-5 powered Eurovan based Winnebago Rialta, & it had about 100 new demo miles on it & the AC was out! Also the Audi I-5 was pretty useless pulling the weight of the camper rear box up the OC Canyon roads near that I-5 Camping Land set of dealerships.
We later test drove a VR6 one in AR during a family trip, where everything worked well & it had much better pulling power.
IMHO go for the VR6 powered Eurovan Westfalia Multi-van/Weekender or Winnebago full camper (a bit larger unit & both are pop-top campers, so you can also go camping & on trips with your kids. We did so with 2 kids up through teens & that included an annual long 4-6k XC trip too.
There are a few VR6 Rialtas around (a Class B or C Full-on Camper IIRC), but they're sorta big & less mpg for DD use, but you'd be the popular Dad with the "hospitality Suite" at all the kids' games & practices!
The VR6 will also give you some modest towing capacity for around-the-house projects' materials, small boat/jet-skis, etc.
I'd also suggest you look at old Consumer Reports for which years had what problems, and ask a good local VW/Audi independent mechanic which years to look for, what typical problems & have him PPI whatever you're getting (if auctions, maybe he can go with you?).
VW & Audi were NOT stellar quality during the 80's & early 90's - so you have to go into it with open eyes, as we did when we bought our 88 Westy Vanagon new, & it has ended up costing 2-3x as much in maintenance as our also new bought 85 BMW 325e 2dr coupe since that time. Ours is an Auto/AT for my wife's DD, & both kids learned to drive in it, before moving up to manual trans.
I think Eurovans were slightly more reliable after the Vr6 came along.
Good Luck!
Tom
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