F5,HardRock or RockHopper
I am getting my chunky monkey butt back into riding and I need a good starter bike. I am 6'1 and 310#. I went to the LBS and looked at the Hardrock sport disc and the rockhopper disc. The shop guy said he would nock the Rockhopper down to $600 to be competitive with a Cannondale F5 I saw at another shop. All bikes are stock. Which one would be the best for me to ride basic trails on? I like all three but I want something that will last and grow with me when I get a little braver on the trails.
Buy the one that fits you best. If they're all equally comfortable, buy the orange one....
In a given price range, there's not much difference among different mass-produced bikes. The market is so competitive that nobody can afford to put on a vastly better derailleur or use much better wheels. They may cut costs in different places--one bike may have a better saddle and another a better bottom bracket or tires or something--but nobody can break away. You may find minor differences in geometry or small variations in top tube length or whatever, but that's about all. Buy the one that feels best.
IF you haven't ridden for years, you might want to pick up something like a used RockHopper or similar. Then you'll have time to get some ideas from first hand experience about what you want. Your needs may change if you get in better shape. Upgrade then.