got both; Y will be my main one..about 5 hours in one badge my party is
Pikachu lvl 18
Charmeleon lvl 18
Fletchinder lvl 19
Riolu lvl 19
Frogadier lvl 21
Combusken lvl 21
once you get the exp share everything becomes quite easy
and yes half my party is weak to water lol
EDit: didn't even know you could turn off exp. share, turned it off noe