Well, I have a 990 and it's large enough for "Just me" solo, so I would think, between the two, the bigger 992 would be better.
If I remember correctly, the 992 is what? 2' longer or something like that? Sorry, don't remember. They, dealer - excellent by the way, advised that for solo the 990 is and will work fine, and it is.
With 3 others, it might get a little crowded so bigger might be better..
I'd feel almost "Crowded" with an additional person, it would be tight but manageable.
It's really just getting used to it, good luck.
Hope that helps a little.. but in your scenario, I would think bigger is better...
Happy trails, sounds like an adventure of a life time..
Frank PooleRoam'n ROG (Full Timer since Oct '15)
2016 RAM 5500, C/c, 6.7 Diesel, AISIN HD 6-spd, 19.5 DRW, 72 Gal fuel, 4x4, 10โ Alum FB, 440 Amps, 4.10 Axle
2016 AF 990 640-Solar/10-6v Batts
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