I just bought the Autana, my wife loves the covered entrance and so do I. I was on the fence about a Kukenam vs Autana for literally 4 or 5 years before I finally pulled the trigger. I was debating how much I'd actually use the annex, is it worth lugging around, is it worth the time? Yes! It was awesome on my 3 day camping getaway. Two of my friends slept down below one night and when we got sick of watching the fire we put my Mr Buddy in the annex with 3 chairs, ice chest and camp table, we hung out for hours in 67 degree warmth vs 32 outside. Its great for dogs, especially if you own a 75 pound German shepherd, changing, dirty boots, what ever. And if your not feeling it, leave the annex at home. Its really a great option. As far as ruggedized goes I could see the benefit in buying one, especially if you use it a lot and your family will be joining you often. Undoubtedly it will handle the constant traffic better, I think the biggest plus would be the beefier floor if I remember correctly. In all honesty I think you'd be fine with any Tepui that suits your needs. I'm confident the overall materials and construction of any of the "non ruggedized" models will give you years of good use. I don't know for a fact how much of the tent is serviceable but it looks pretty modular incase something ever wore out or broke. Thats another plus.
FYI: If you buy a tent...
Probably the best thing, like any fabric, is gently blow it off with compressed air, that way the abrasiveness of the dust and dirt doesn't wear down the fabric and waterproofing when its stowed away.