Honestly, for me it depends on how much you hate horses. For me, it is a pathological hatred that extends into every build so I use the Poleaxe (as well as the Poleaxe master of cRPG suggesting it to me), so the reach helps with that sexy stab.
I used both and just settled on the one that fit my play style before, though sometimes I swap back for a few rounds because I like to facehug dance so much. I also use the thrust animation a lot as I am good at aiming for the face, so again the standard poleaxe was chosen. Lastly, my polearm build is 24/15 so the extra reach helps negate the low athletics, and I have yet to fall victim to those mythical back-peddlers (though that is a garbage tactic against anyone who knows what they are doing anyways). Without that extra reach I don't think I could fend off and delay 4 or 5 guys like I am often forced to do.
Just remember that with both weapons they have that lovely spike on the end, so your reach is significantly longer then it looks at a glance. You can get in countless free hits if you get used to the weapon.
