ask yourself what you REALLY want out of a boat. waterski/board/surf/tube/swim. the outback will do all those good, but it's really a crossover boat. the mondo will run circles around the outback from a wake/surf perspective but is not a slalom boat(chalk that up to the outback). it also has a somewhat tall freeboard that might be a bit of a challenge for younger kids to get in/out from the swimdeck.
best advice is to go try each and you will fall in love with one..

my vote for a young family will be mondo every time as it will offer more wake potential as the family grows up, but it's my .02..