I have a Kona for my HT and a Spesh for my dually, so no personal knowledge of either bike, but looking at these two there is not a lot between them. At a brief glance they look to have pretty much the same spec for fork, frame and similar levels of componentry other than wheels and brakes.

While some people love their Avid Juicy brakes, but plenty also don't. And the Tektro Auriga Comp have done a good job on the bikes of a few people I know, so I suspect it's more a personal preference on feel or a brand loyalty thing and you could flip a coin either way.

If it were me I probably wouldn't cough up the extra $$ if I was happy enough with the feel of the brakes and if the wheels were of similar weight on both bikes. The cheaper ones are still eyeleted (a must for disk brakes)and a reputable brand.

For my money, if all else is the same, I look for a decent fork (they are the same) the best rear derailleur in the price bracket (both Deore SL) and a minimum standard for wheels and brakes (which they both meet). So much of a muchness really.

FWIW I got the Spesh Fastrak tyres on mine when it came and am not a fan. I find them way too slippery, not good at shedding mud - really only nice if you are riding in hardpacked tight surfaces where you want a progressive slide rather than good bite. I got somewhat sneered at by the bike shop for changing back to a much grippier, versatile and robust (and yes - heavier) Maxxis Ignitor for a more reasuring ride. I don't need the ten tenths of speed on the dirt!

Good luck and i hope you enjoy your choice.