My consistency vastly improved with the purchase of lead sled. Your hold is more consistent and even a magnum does not beat you up at the bench. It was some of the best money that I ever spent.
Be careful with a lead sled as it may create some strange effects. Always verify POI after using a lead sled as they have very little recoil forgiveness and I've seen 2 Big Boomers that ended up with cracked stocks. Depending on how you set them up and how much weight you use for resistance it can be almost like putting the butt of a stock up against a tree and then touching one off. They can be very unforgiving on recoil lugs, bedding, stock etc. depending on the amount of recoil as those components are taking the vast amount of recoil - only time will tell. I personally will not let one of my rifles used on a lead sled but each to their own.