For the money it is pretty tough to beat the Caldwell "Rock". I also like a tall rabbit eared rear bag filled with sand. I also have a very heavy BR front rest. But it simply is not practical for most shooters, and most shooting. And it is stupid heavy, and very costly. I would not recommened it for the average guy.
The Lead Sled is OK for short range work. And for light recoiling rifles. But for long range work it simply does not allow the rifle to recoil naturally. And field shooting POI will change(long range shooting-not100 or 150 yard shooting). Although POI will also change at 100 yards for the heavier recoiling rifles.
I have no use for a leadsled. I want to learn how to shoot. If not I would simply buy a vise and lock the rifle down. Or shoot an extremely heavy rifle that moves very little. Tom.