I had a Cashel Softsaddle. Rode in it ONCE. I sold it. I did not like the way the flaps would roll up under you when you bareback mounted, you know, flopping your tummy onto the back, then shimmying around to be astride.
Also, the "handle" ends up under your special parts and that feels bad!
A good treeless saddle will cost you. I have seen some nice looking Bob Marshall western saddles, and the Ansur seems nice. I would not use a treeless saddle for riding if gong long, long distances but for putzing around I think they would be fine. They do, however, usually requiree special pads to create relief for the spinal column.
Ansurs are nice, but pricey. A new saddle will run you a few thousand, but you can find very good used ones for $1500 and under. Freeform, Barefoot, Black Forest and Torsion are all popular treeless brands. Personally, I'm saving up for a Barefoot Tahoe Classic.
MANY endurance riders ride competitively and win in treeless saddles - so they can clearly be good for "long, long distances" (I'm talking about 50 and 100 milers).
Treeless saddles do have to be fitted.
They don't all require a special saddle pad - it depends on how the saddle is built. Some dealers will recommend what pad to us with the saddle. SKito, Toklat and HAF pads are the ones I hear most about, but there's others out there.
Another option to consider are fursaddles, but those are more popular in Europe than in the US. Good ones will cost you every bit as much as a nice treeless saddle though.