There's no substitute for quality suspension. I've got the "dune edition" fronts from Elka for an EX, and some stage 3's on another bike. While the base models are a significant improvement from stock, they are not worth the money that they go for. If you think about it, spending 400 on a nice used set of quality shocks, and sending them off to get rebuilt for you, is extremely cost effective. You may end up spending a little more than your budget, but in return you get shocks that someone else is paying over 1G for, at about half price. With the high price of shocks, if I'm investing in something that substantial, I want something with the best return, and minimize my opportunity costs. To me, it just seems well worth the extra money and time.
Even as a recreational rider, the last part of my bike I want to reach the limit of (other than my brakes of course) is my suspension.