whats your bodyweight?
Last time I did it, I was about 240 at 6 feet.
Don't do the high reps too much because to get the most reps, you have to do it at the beginning of a chest work out, which pretty much screws up the rest of the workout.
What I do do is reps of 20 to 30 with 225 at the end of the chest workout to get a good pump going. This "training" is probably why I can hit so many at 225 when fresh
Back to dips, definitely the strongest on these, i've done 3 reps with 235 around my waist at a bw of 235...total of 470. That was scary...felt like my arms were going to tear off