Buy buy buy!
I can't say enough good things about this bike, just search for posts by/with me and the word "Hardrock". I've put nearly 3,000 miles on mine in the past two years, starting around the 420lb mark. Mr Bad Mofo has only left me stranded - kind of - once, but that's almost my own fault because ole boy gave me plenty of warning. Here's a pic:
Saddle: Specialized Sonoma 155 (GREAT change)
Pedals: Wellgo "BMX platform" (if you have huge feet, they should be a requirement)
Brake Pads: Kool Stop dual compound salmon/black (again, should be required for us big folks)
Tires: Specialized Nimbus Armadillo (COMPLETELY change the character of this bike, it really rides like a dream with these)
Crankset: Shimano Alivio (stock one gave up the ghost at about 3,000 miles, can't say I blame it..
Whilst cleaning it on Saturday, I discovered some pretty nasty cracks in the rim, so it'll be getting a new rear wheel soon. But seriously, here's the deal. I weighed about 420lbs when I got it, beat the snot out of it for a year. Got another bike so I relegated the HR to rain/offroad duty where it got even more snot beat out of it. Then this year while awaiting a new bike, I rode it for a month or two as my primary commuter where, you guessed it, I beat more snot out of it. I've broken some stuff, sure, but for $350 (what i paid new for mine) you really can't go wrong AT ALL.
This is one bike I'll keep forever, just because it's one I always know I can just jump on and take for a blast.