There are quite a few target manufacturers. I know I have at least one here in my home state that's fairly popular.
The one thing I like about the PT series targets is that they have no holes drilled for mounting hardware. There's nothing really to break or to wear, and it's safer to shoot steel with a handgun at close range if you don't have chains, bolts and other objects in the path of the bullets that can cause an unsafe deflection of a round.
I also like that the Action Targets are made of AR550 which is considerably harder than AR500 commonly used. That means even more durability and extended life with rifle rounds.
But yes, there are other options out there for steel targets. I've had some pistol targets (not Action Target) that are at least 15 years old now and still going strong.