Welcome aboard litehunter. I use adjustable blocks on most of my AR-10's, but that's more for suppressor use than recoil. Though it does help, as you can adjust the right amount of gas that you need. Overall, alot of it comes down to personal opinion or reason for use. They're easy enough to swap out. Doesn't hurt to try, if you're willing to spend a little cash. Some aren't really that expensive.....relatively, of course.