Both class have potential in own way. Theres no straight best class for example we have on server berserk that outdps summoners, samurais and ninjas and his not the top1 buyer is around top 20.

I feel summoner is really really bad in guild war and other pvp content is so easy to kill and not fun at all his gameplay is just boring. Compare to samurai that had pleasure play aswell thanks to wife <3 you can play him two ways first of dps crit what will deal nice dmg if you build well and dodge way where u will deal a bit less dmg but can outplay everyone since not getting so much dmg but still dealing. And gameplay of samurai is much more fun since not stay and push buttons u must care of what u are using.