Problem I had with 409's was my lead foot. Scattered a lot of them over the back roads around my house. The 409 passenger car block I was using in an attempt to build static compression doesn't have a very strong bottom end (main webs and rod bolts were really weak).
Today you can not run 11:1 static compression because pump gas will not support it, so the scallops cut to reduce static compression on a truck block are not as critical with 87 octane gas. The scallops on a 396 was cut to clear the valves (they would actually hit the top of the block otherwise), but on a 409 it was just too kill compression.
Today we have aftermarket chrome-moly rods with ARP rod bolts that are twice as strong as the stock Chevy rod bolt. You can run ARP main studs with a main cap girdle to strengthen the bottom end to make those 10,000 RPM shifts to impress your friends.