I stump shoot weekly but seldom shoot at stumps.
Use judo's and shoot at leaves, grass clumps, pine cones, there are a million things to shoot at other than stumps that are not hard on your arrows and are better practice and by the numbers, offer way more shots.
Plus its Mich easier to explain where you are aiming when stumping with a buddy if you shoot small easy to identify targets. Its harder to explain where the good hit is on a stump.
If you are gonna shoot at stumps look for rotten or old stumps not new or fresh ones. I personally think you should be stump shooting with the same arrow set up you hunt with so the arch, trajectory, feel, etc is the same. This makes stump shooting (even though shooting very few actual stumps) the best practice for a bowhunter.
I think a lot of people shoot at stumps because they think they need to shoot at something that stops their arrow. The judo is the backstop! Its the judo that stops the arrow. The target can be anything from a hanging acorn to a side of a mountain and everything in between.