I was by the Erie Canal and trying out my new Ace 350. It hit really large, so I dug down. Then more, and more and more until I was about 2 ft down and hours to dig it up!
Not super interesting, but the largest thing I've ever found.
I think it's cool that you put the effort into digging it up, just make sure you aren't doing giant excavations on public land where people will get mad at metal detectorists. For the most part, if it's a giant find, it's only worth it's weight in scrap metal. It's different of course if you are relic hunting. But I try to leave the pipes and tires in the ground when I find them.
The biggest thing I found with my MD was a 1938 Texas license plate that just happened to be directly under a fully buried cinder block. The top of the block itself was about 3-4 inches below the dirt. Took a lot of digging there. It was a neat find though, as it still had half of the original yellow paint on it even though it was heavily corroded.