Which is the Fourth tier on the Shimano system for Mountain Bikes (Behind XTR, XT and LX Components, through technically XT and LX are "Deore", the proper name for each is XTR, Deore XT and Deore LX and then Deore without any lettering).
Now in the Shimano Listing they mention Saint and the Hone but these are for heavy duty racing MTB, so I do not count them among the "tiers" of Shimano Mountain Bikes Components.
For Shimano list of Mountain Bike Components:
http://bike.shimano.com/catalog/cycle/products/category.jsp?FOLDER%3C%3Efolder_id=2534374302039898&ASSORTMENT%3C%3East_id=1408474395181419&bmUID=1150509453900Now one of the Complaints against Shimano is that they change they product on a regular basis, more to make old systems obsolete then any real improvement (For example Shimano just announced it has completely re-did its XTR line). This constant replacement regime is why a lot of people stay away from the high end XTR components, but the system does tend to work to slowly improve the parts.
Anyway back to the KONA, except for one Shimano XT part (and that is in the Deluxe version), the parts are just Deore (Not even LX).
Now on the Deluxe model the hydraulic brakes are Haynes, and that is one of the top makers of Hydraulic Brakes. The problem is will you need Hydraulic Brakes? Hydraulic Brakes came out of the need for Mountain Bike Racers to stop dead in the deepest mud. Hydraulic brakes are thus not affected (or more actuarially. much less affected) by Rain. Thus if you are going down a steep embankment and have to make a sharp turn at the bottom of the hill if it is raining cats and dogs, you will notice that the hydraulic brakes will slow you down almost as fast in the rain as in dry conditions (unlike conventional Brake that are affected by Rain in that it often takes a while for the Brakes to dry off the rim to slow down the Wheel during heavy rains).
On the Hoss itself, it has Shimano Non-Hydraulic Disc Brakes. These are NOT as good as the Haynes Hydraulic but do you need disc brakes? Let me give you couple of Example. I often peddle with a trailer that has 50-60 pounds of Camping gear in it. One of these days I will go bike Camping but I have Not done so yet. Anyway back to the subject, I have had NO problem hauling this wait and stopping this rate in my Home Town of Johnstown Pennsylvania (and that includes going up and down the various hills in this area, I notice the weight when I am going uphill). The only problem I have ever had was last year when I took my bike and Trailer down Chestnut Ridge in US 22 In Westmoreland County Pennsylvania. I had NOT check my brakes prior to the trip and after hitting the brakes for about four solid miles downhill they started to wear out (I Should have replaced them BEFORE that Trip). Even then the brakes had slowed me down enough WITH THE TRAILER BEHIND ME, that I could stop the Bike with my Foot and check out the brakes. It is the only time Disc Brakes would have been better than regular brakes (and I checks the brakes, realigned the pads and continued on my way).
My point is Hydraulic Brakes for most people are NOT worth the extra expense of such a brake system. Furthermore Disc brakes (Both Hydraulic and non-hydraulic) add wait to the bike that by itself makes the bike harder to peddle (and this is from a person who has front and rear Panniers on His bike, you add weight you will notice it peddling). As a whole I do NOT think Hydraulic Brakes are worth their cost FOR PEOPLE WHO ARE NOT RACING OR GOING UP AND DOWN MOUNTAIN SIDES ON PATHS (not roads) In Deep Mud, during Heavy Rains etc.
As to the front Shock it is also a Name Brand. They web site follows:
http://www.marzocchi.com/spa/mtb/?LN=UK&Sito=mtbOn that site the Shock is about half way through the list, so it is not the latest Cutting edge, but it is an effective shock. The issue on Shocks is where are you raiding? Off-road? Then a Front shocks makes sense as you hit rocks, stubs and tree roots, but if you plan only to go on paved roads the extra weight (and costs) of the Shock makes no sense. The few potholes you will hit with the bike just do not (in my mind) justify a Front Shock. FOr example I took the Shock off My bike and replaced it with an Aluminum front fork, a lot lighter than the Shock it replaced) for I saw no benefit to it if I stayed on Paved Roads or Bike paths. Saying that it looks like a very good shock for someone who wants a Shock but plan to stay on bike paths and paved roads (Please note the shock adds about 2 inches to the front end of a Bicycle and most modern Bicycles are designed around a shock on the front, thus if you opt NOT to have a Shock you may have to get an adjustment to raise the handlebars the two inches missing when you replace the Front Shock with a Non-suspension Front Fork).
I do not want to belittle the bike, but you asked for comments, both good and bad. You might still like the KONA for the price and then upgrade the components later on, but the Components are NOT the best for the Money (The XT series is in my opinion the best for the money) but they are NOT junk either, they are GOOD COMPONENTS. The real issue will you be happy with a Ford, when for just a few dollars more you can have a Mercury? (For you GM drives out they, Will you be happy with a Chevy when you can have a Buick for just a few dollars more). Notice I did not say Lincoln or Cadillac (that is the XTR and it is over priced for its limited improvement over the XT series). The XT and even the LX series of Components are just so much better for just a limited increase in costs that, In my opinion, upgrading to the XT Components may be the better option.
One last statement. Remember you are a consumer, sometime you want something new, even if rebuilding what you have would be the better choice. If you THINK the KONA is the better choice than upgrading the Giant, I would tell you to go with the KONA. If you opt for something you dislike, you will dislike the choice no matter how much "better" it was. Keep that in mind when you decide. What would make you more happy? That is a more important question then what would be the "right" choice.