The Yukon sits near the top of Giant's Sport ATB range, which sounds a bit 'hybriddy', but its only concessions to town use are frame fittings for a rear rack and tyres with what's almost a centre rolling strip for Tarmac work. Fundamentally it's still a mountain bike.
The frame is one of the bike's strong points. Fluid-formed aluminium is shaped into a buttress at the top of the down tube for strength, while the wishbone seatstays and chunky chainstays are decently stiff for the job - stiff enough either for panniers or for heavyweights stomping on the pedals, anyway.
Spacer washers put the bars high to begin with, and the good news is that this gives you lots of room for fine-tuning. The bars don't offer the same slow speed technical steering as the Mongoose's wider ones, though.
The fork is adjustable for preload only, yet it's the firmest here. On pedally singletrack and rock gardens it allows you to move your weight around the bike more freely, without fear that sudden squelch or rebound will upset your balance. It's predictable downhill too, although there's a deadness to its climbing feel that makes you think it's heavier than it is.
The 24-speed drivetrain has the offers a good range of gears and you don't miss the smaller steps on the trail. Hayes discs do a good job on the kind of long, fast descents where well-used V-brakes struggle. Finally, it's worth noting that the tyres are summer issue and struggle in mud.