Well, the Citi Prestige has a very good signup bonus (275,000 Citi points, worth 110,000 KrisFlyer miles). It has a $700 annual fee, but you also get unlimited Priority Pass lounge visits. The everyday earn rate isn't as good at 0.4 KrisFlyer/$1 (compared to Suncorp Clear Options Platinum at 0.5), but Citi's bonus points for certain spend categories are good if you're spending a lot at supermarkets, restaurants, petrol stations, airlines etc. Both have no caps on points earning.
Basically, I'd say go for Suncorp if you want a (much) lower annual fee at $129 and a better earn rate for things that aren't bonus categories on the Prestige. The sign-up bonus also isn't terrible at 120,000 Suncorp points, worth 40,000 KrisFlyer miles.
Go for the Prestige if you want Priority Pass and a better sign-up bonus.