Thinking about joining a senior league where they only allow single wall bats. Haven't used one in years! What's the best single wall ASA bat for distance? Thanks for any help.

Irishmike, the single wall bat of choice here is the Demarini Steel, however one local league allows it and a neighboring local league doesn't so verify with your league. most recent model was the 2016.
Not sure if they are coming out with anything newer.

What about the Easton Ronin alloy bat, anyone swung that one?

I play in a very large league in Southern Calif.,which allows only single wall bats.I can tell you that 90% of the guys use the 2016 Demarini Raw Steel. I use it myself and it is the best single wall out there,and when I see somebody using something other than that,it's usually one of the older model Demarini Steel models.I did buyan Easton Ronin single wall,butdon't have enough hits on it to give anyone an honest appraisal.

Anyone have feedback on the endloaded Anderson Flex

Thanks everyone. But my league tells me we can't use the Demarini Steel. Ant thoughts on the Anderson Flex?

Our league is a single-wall only league for those under 70, and we have discussed banning the Demarini Steel because of its extraordinary pop. Any thoughts on why it is so hot?

It’s possible that this is one time that the manufacturers marketing hype has merit.

Using steel for the barrel allows for thinner walls that provide more flex without cracking.
Normally the extra weight of steel would be problematic. But they compensate with a light weight composite handle.
IMO

I broke a Steel recently and cut it open to see what the endload was and found virtually nothing. Just a plastic cap.

"Old School" Demarini Ultimate Weapon if you can find.

“ broke a Steel recently and cut it open to see what the endload was and found virtually nothing”

Yerwombat.
You may be able to provide some measure of explanation for your observation.
If you were to piece your bat back together and measure its balance point , you could compare to similar weight balanced and endloaded bats.

I don’t know the answer for any of the demarini steel flavors.
But, the barrels of those bats are really composed of steel as opposed to aluminum. The density of steel is considerably greater than aluminum. So steel barrels would likely weigh more than comparable aluminum barrels.
The result would be less opportunity and/or need to provide additional endloading.
IMO

Our single wall league has also banned the steel.
Lot of folks still use the ultimate weapon.