"UK trails" is pretty meaningless tbh, glentress green and laggan black and fort william worldcup and my 10-mile pentlands loop are all UK trails.
I thought I'd really like the ST4, it seemed like my ideal bike at the time... But I got off it thinking that it climbs much like a five, and descends worse. Just couldn't see much point to it.
To be fair that was an old ST4, it might have improved since (though, did they not neuter it last year a bit?) but it just felt like a missed opportunity.

