Well team Straddie clearly a nose in front with one, but early days I guess .... 
Forest
straddie, but more expensive than Bribie.
however its free trailers until August on the straddie flyer, so only $149 return.
camp fees are more expensive than Bribie, as the indigenous people run their own organisation to manage the park rather than the national parks.
all up more expensive, but better.
remember though that all the schoolies decended on straddie and rioted one year - so you cant get away from all the bogans and nitwits.
queens bday long weekend I would totally avoid bribie, but I proved a month back that during the week it can be real quiet and quite enjoyable camping on bribie (ocean beach).