I have no experience with this specific setting, but I've played SW quite a bit. I think it would be pretty straightforward to adapt it to FATE, and with a little extra effort but a better result to Cortex Prime.

I also bounced off of the Reloaded version (and SW in general). Unfortunately, I can't really speak to the alternatives from personal experience.

However, I've been gearing up to try Call of Cthulhu, and found out it has a Western setting! Down Darker Trails. I had never heard about it, but what I could find was really positive. If and when I run a weird west game, that would probably be my first choice, and certainly a top contender.

I haven't tried it out yet, but the cypher system seems like a good fit.

It did not work for me either. Savage Worlds is not adapted to gunfighting in my opinion, and my players were also more demanding regarsing horse riding stuff... Still looking for a good replacement, but nothing is available from the shelf it seems