“Gaited horse saddles” are a pure marketing ploy. Don’t get “fished” by the sellers of “snake oil.”
Lee Z., if she were still with us, would agree. 
I, too, ride a Stubben Scout. It’s a very comfortable and practical general purpose saddle. It is not cheap and they are difficult to find used. The original design was based upon a saddle Stubben made for the Belgian Army after WWII. It is used by other militaries and many police organizations (both here and abroad).
My wife rides a Stubben VSD-DL and she is happy with it (although she has recently started talking about a Giacomini saddle; sadly those are REAL money even though well made and comfortable).
Like Tamara says watch out for the bit with a horse with lots of head nod. I don’t have any aggressive “nodders” right now (nor any TWHs for that matter
). I like the Myler Bits; I’m presently using a Pelham with a low port mouthpiece.
With any saddle you’ve also got to consider the padding. The Scout is well padded. I’ve found a Civil War era blanket I bought from the Blockade Runner in Wartrace, TN (folded cavalry style so that you get six layers of blanket) works very well. Your local Pendelton Wool Outlet is also a good source for excellent quality blankets for about $50.
Whitman also makes a police saddle that has many users in the U.S. I’ve never sat one but a couple of folks I know who use them say they are a good product.
Two other types of saddle that can work very well are the McClellan (generally called a Mac) and the British Universal Pattern (generally referred to as the UP). Don’t try using a historical Mac or UP as they were optomized for the 19th or early 20th Century horse (and don’t generally fit the 21st Century “sofa bred” type of conformation. :lol: )
They are very light weight and many find them very comfortable. Personally, I’ve never liked the Mac but maybe it’s just me. Lots of used ones are around, but be VERY CAREFUL to ensure you get a quality reproduction from someone like Doug Kidd (Border States Leather) or Tom Smith (Tom’s Cavalry Equipment). I’ve seen he work of these guys and it’s excellent. They are not cheap, but a good saddle won’t be. A cavarly blanket under these saddles generally all you need for padding.
IIRC the Trooper saddles that are presently being marketed are direct desendants of the the UP.
Steele makes a very good quality saddle. They are mostly of the Plantation or Western design, but I think they also make a Buena Vista style that some gaited folks like.
Personally, I don’t like Aussies (never found one that fit me) and consider the “treeless” saddle to be an instrument designed to sore a horse’s back. As with all things, YMMV.
Good luck in your search! 
G.