Completely different bikes? Ones a xc whippet, the other an AM/trail bike
Depends what you ride...
Definately agree with this. You could really do with workin' out what you want the bike for, otherwise you could end up with a right costly mistake.
I had a quick demo of a Top Fuel and Giant Anthem X a couple of years ago, and bought an Anthem X - I was after a fast full-sus XCer, but the Top Fuel was too similar to a previous XC full sus bike I'd owned -excellent for a skilled rider and XC racing, but very little margin for error - loose concentration for a nano-second, and you're on your off!
I also currently have a Stumpy FSR Carbon Comp - it's a totally different beast to the Top Fuel. Quite a forgiving bike that has the potential to appeal to a broad range of skill levels (er..again only IMO!). Being the type of Trail/AM-ish bike it is, the Spesh is softer and 'ploddier' uphill than the Trek, but on descents, rough, and fun stuff, it'll leave the Trek for dust. In stock set-up, the Spesh has quite a beginner friendly tall front end - TBH, it's not too bad for general trail riding, but if you want to get some more bite from the front end and a feel for what the bike is really capable of, put a shorter low rise stem, wider bars and a sticky compound front tyre....and unleash the insanity 
the bike really comes alive and has a playful feel about it, without getting twitchy (it's dead easy to pop manuals and hop off and over things).
Only thing I've found really annoying on the Spesh is that the rebound knob on the shock can move by itself every time the Propedal lever is switched on & off; so, if you're not aware, it can end up at almost full fast rebound towards the end of a ride - I've stopped using Propedal now, and unless it's a real long tarmac ascent, I don't really miss it!
HTH
