On KitPvP you can have fully enchanted Prot 4 diamond armour and be against someone in unenchanted iron armour but the Prot 4 takes time to get :p
On Barebones, the fights are fair and you get rewards at the end of every season ( end of each month ) if you are in the top 50,20 or 10.
Of course the higher your rank the better the reward.