The 300/400/500 is actually one of my goals. At the moment I'm at 300/350/425. I'm going to try an hit it this year if work and grad school don't get in the way too much.
As far as the long limb comment above, I think it can have some affect. I have long arms and really don't think I'm ever going to go much more than 300lbs on bench. Just doesn't seem like my joints, bones, etc... want to let me do it. But my long arms also gives me some good leverage while DLing. I feel confident that one day I'll hit the 500lb DL. Full squats were a bit tricky, but once my ankles, hips and hams became flexible enough I started feeling confident about hitting a 400lb full squat one day

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