Over at AllOutdoor Major Pandemic writes about the benefits of installing an adjustable gas block on an AR-15 rifle …

This last weekend, I provided a buddy a side-by-side comparison of his standard AR and one of my AR-15s with an adjustable gas block. His actual quote was, “Holy crap. When can you do that to mine?” Your first experience with an adjustable gas block will be an enlightening one. The near absence of recoil and almost non-moving sight picture is stunning to say the least, in the “Holy crap, why did I not do this before?” kind of way. I maintain that an adjustable gas block is the most significant performance upgrade anyone can make to their AR format rifle.

After my very first JP adjustable gas block, I was sold on the having the ability to tune the gas pressure on a standard direct impingement AR-15 system. The advantages are a plenty: a large reduction in recoil, faster recoil recovery, faster sight picture acquisition between shots, heat reduction at the bolt, and a bit cleaner running.

What are your experiences like with them? Are they worth having?