A380 or 787?

I'm considering the direct flight between Denver and Munich which can be booked through United, flying on the Boeing 787 or flying the Airbus A380 that is a code share with Lufthansa? Price and times are quite similar. Any advice or opinions for which one might be better in terms of comfort and customer service? Also, if I have platinum and we're to book the Lufthansa code share, can I get economy plus type seating without paying extra?