Ok, I've enjoyed reading the banter thus far, and although I'm certainly no expert, I do have an opinion based on years of riding and working on both manufactuers frames.
The true tale of a bikes quality is not in the shiny paint or flashy decals, although they make us feel good/excited about the frame, but the unfinished product beneath and the story it tells of it's creation.
Fat's, all the fan hype and love aside, were excellent manufactured frames
... I say that because the majority of the bikes produced were not handled by Chris and a few close craftsman, but by many hands that repeated the same process on each frame to create a finished product.
It is in the passing of hands that the details of fine craftsmanship are lost.
I've worked on a number of Fats without paint and there are some alarming mistakes present that should not be excusable on a high end frame; tubes that are not aligned/placed in plane prior to welding, braze on's that are in fact only tack welded and never finished, drilled vent holes in tubes in the vertical plane that are forgotten and left open, welds that have porosity holes from increased internal gas pressure, etc...
The majority of the Fat frames were never even blasted prior to paint to insure good mechanical adhesion, thus the poor paint durability.
Speaking of paint, even on a few NOS frames, I've seen areas of the frame that have not been painted (underneath the seat stays, under the canti hanger).
Now, when you are cranking out the number of frames a year that Fat was, mistakes do occur. Hell, even on custom one off frames it happens. But the pure number/frequency I've observed is a bit unsettling.
As for design, Chris did put a lot of effort into this, as he took time to spec custom tubing and shapes to insure the finished product rode like he anticipated it to.
As for Konas, the majority of the line served it's purpose; to hit a price point market with a product that generated consumer contentment. The TT Hot's were another matter. We had the pleasure of sharing building responsibilities of the Brave Cycle frames for Doug Gloyd with Tom. He did a few runs as did Grove. Tom's work was detailed oriented, precise, and of excellent quality. Although successful, he was always an underated builder, as many of his designs (both geometry and finish) did not excite, but produced long lasting solid bikes.
Strip a TT HOT and a YO and compare frame construction and quality...the HOT will walk away with the honors every time.
FAT vs. Kona...both are held in deep regard in their admirers hearts and will be a contest that will continue for years to come on this board