Well lets be fair, league on average has twice the amount of tackles (av 280 v 122 per game) and plays (av 85 v 79 per game) compared to union, it has less boring tennis style play kicking, its overall a much faster game with more contact due to tackle counts. Also of the only two union v league meetings league proved to be the fitter and better athletes (Bath 6 v 86 Wigan @ league and Bath 44 v 19 Wigan @ union).
On top of that union feel the need to offer stupidly high paged wages to steal league players (Robinson, Harris, Smith, Henry, Orr the list goes on). I think thats enough proof to say which is the best out of the two FFS.
I still like union though as they have a great set-up for internationals, something league struggle to sort out. But club wise league is many years ahead of union.