RE: Block, cube?
I've used the yellow jacket and won't again. Needs a truck to pull them out. Wondered when I shot one if there was some kind of break in period, there was, when it was all shot up. The problem is they have corigated cardboard in side that the bh has to cut away on the way out. Try punching a hole in some with a bh and then pulling it out and you'll see what I mean.
I have currently one of the King targets sold at Keystone country store. Other than it's small size it works well, has taken many a shot and ata good price. Increasing densities of foam seems to work best in a bh target.