2008 Kona Four ... what should I upgrade?

you could go with a new set of light fast rolling tires, maybe a new shimano xt derailleur. Parts are a personal preference. You might want to ask what your friend likes before you buy. You could also go with stuff like a camelbak hydration, jersey, bike shorts, new helmet, if any of that stuff is needed. Or you could do a performancebike.com gift card, something like that :thumbsup:

well I never like giving gift cards because the impact factor of opening up a gift card is just bleh in my opinion.

he's all set on jersey, shorts, camelbak, helmet, etc ... he does need a pair of riding glasses but I feel glasses are very personal choice and I have no idea what he wants other than transition lenses because he likes my transition lenses.

he likes his seating/cockpit position .. was wondering how difficult it would be to get a lighter stem and handlebar yet keep the bars in the same basic position

its pretty easy to get the same size parts to replace. you can refer to this link on getting the stem/ seat post sizes

http://www.konaworld.com/downloads/2008_tech_info.pdf

this is a good quality bar for the price
http://wheelworld.com/product/easton-09-monkeylite-sl-cnt-carbon-bar-31.8mm-diameter-7167.htm