Best for 20 year old- RCCL Liberty of the Seas vs Norwegian Epic?

We are considering a summer cruise from Barcelona. Both Liberty of the Seas and Norwegian Epic have somewhat similar cruises from there. One consideration is which might be better for our 20 year old son?

Would welcome any thoughts! ( He will spend some time in the casino - as will we!)

RCL has surfing, a ice rink, a boxing ring, lots to do for a 20 year old.. happy cruising

We will be on Liberty with my 20 year old Grandson. He loves RCCL ships. He won in the casino last time and thinks he can repeat it on Liberty.

I think both would be great for a 20 year old. I'd call it even there. With that in mind, book the itinerary or whichever ship stands out to you.