Even without having been on an Aliante, I can say with condifence that it's a much narrower saddle than the Arione -- I'm certain, because the striking characteristic about the Arione is that as a horizontal platform, it's about as generous as a performance seat can be. There's very little vertical curve to the thing.
Luckily, the shape of that platform is the key for those who love the Arione -- other saddles have always left me feeling that their narrowness, and the molded vertical drop-offs, leave my pevlis unnaturally straddling a stiff rail that inevitably falls front and center, where there's no bone to hold you up.
This baby is long, it's broad, and for the first time, it's given my bones some real support. Feels like sitting on a chair, rather than a rail.
Of course, that's just me and my crotch.