This year, I'd like to be accurate and confident with 375'-400' drives. My 10s/11s are perfect for this distance and continue to be my controllable D/FW drivers. For open tee shots, I'm using the max weight 12s if there's any wind and I'm using bubble 12s in calm conditions. I'd like to be fairly accurate at 450' with these DDs. In good conditions though, the bubbles crush them all. Just sayin'.
I maxed out at 510' in a D contest (with a 10mph tail wind, pretty sure we were throwing destroyers that day) in 2008 shortly before having surgery to relieve a pinched nerve from a herniated disk…go figure. In my opinion, anything over 425' is all about hitting the right line/height for the chosen disc, assuming your technique is sound. Find the line, and you shall have your 500'.
And as far as technique goes, you can read about it all day long but it really boils down to "feel", the result of TONS of field practice. It's trial and error until the very first time you put a good move on the disc. When this happens, when your timing is perfect and the stars align, the off-axis torque will be noticeably mitigated and your rip finger will feel like the disc weighed about 10 lbs as it tears through space-time at warp speed. Pure, unadulterated magic. These flights are often followed by a fist pump and a wide smile. From there, it's all a matter of breaking down and understanding that feeling and duplicating it.