they are both good in regards to content and game play not to put you off island paradise the world does have lagging/routeing issues (search the forum here )BUT you can use the content that comes with the island paradise on your home lot in whatever world you normally play in the fire pit, boats ,the pool bars etc in island paradise it's self you can live there and do normal sim things or start off if you want to own and buld up a resort or just stay at one for a few days(get the free resort hobarts if you want to see what owning and building a resort is all about don't like it sell it ) go scuba diving find and become friends with a mersim eventually if the friendship is high enough you can mermadic kelp form them eat and become a mersim
uni your sim can earn degrees if you want to send them to uni (you don't have too ) new plants , the chance to get a plantsim,become a plantsim or plant a forbidden fruit harvest it for to get a plantsim baby , bowlong ,ping-pong most of the machines for example the research station you can buy in buy mode and use on the home to research again you don't have to travel to the uni world if you don't want to
uni is a sub hood much like world adventures, a mascot will turn up at your lot you clcik on the bucket take apptutude test then enroll in uni for one term or two roughley one to two sim weeks again you don't have to go to uni if you dont want to but if you do before you enroll to go to uni save your game then save as new name in case something goes wrong or your sim goes invisable you'll still have your previous save to go back too and lost much in playing time