You know, I like to run off at the mouth, there's no denying that. That 500# DL comment was one of those moments. But, chances are that if you don't think you can get to a 500# deadlift, you're not going to do so. If this is a concern of yours, my suggestion is to seek out a local group of powerlifters to lift with and to loosen up on the diet a bit to put yourself in a state of positive energy balance.
Won't take anything away from your prodigous mouth but I have heard the 500 number in a lot of places. For a legit strongish guy,the 500 pound benchmark (or thereabouts) is reasonable. I have no question that I will get there....slowly. The 405 front squat.....a bit iffy.
I ran across a discussion that you may have been in that 3(00),4(00),5(00),is a legit and workable goal for the 3 power lifts. These number are in line with the ranges that Rippatoe has in the back of Practical Programming for an advanced (competitive) but not elite (winner) male lifter in the 198 class.
Goals are good, Standards are good. I'm a hell of a lot better off from the tsruggle of reaching for 500 than from being smug at 405.