the trance is too high ratio for a 275lbs rider. you'd have to run so much pressure that the rebound and compression circuits wouldnt stand a chance.
you need to look specifically for a lower ratio bike.. this is the relation between shock travel and wheel travel. a bike like the trance has a 38mm stroke shock and gets 107mm of travel out of it. 2.8:1! you want something under 2.5:1. a 100mm travel bike with a standard sized 7.875x2.0 shock is 2.0:1.. might have to look towards 125mm bikes for a 2.5 ratio. still reasonable, just keep it around 2.5 or less. this does unfortunately rule out some bikes, but theres still plenty that work.
id plan on getting some GOOD quality wheels built for whatever you're going to ride. this doesnt mean heavy boatanchors, but quality rims with quality hubs laced up by someone who knows how to build a proper wheel (or do it yourself, its not too hard to learn!). this is critical.
i dont think any company warranties breakage.. seems like everyone offers a defect warranty, but hammering a frame to death isnt a defect. MANY companies will stand behind their product and warranty abused and broken frames nearly without question, but its not a no if-ands-or-buts unconditional warranty.