i would pick the wrx because: 4 doors (trips with friends) already boosted, awd, reliable if its not ghetto rigged together, doesn't need much on maintenace than any other ordinary car if its not ragged on all the time, good winter cars
s2000: its a honda, convertable, rwd, very very comfortable seats, clean body style, good gas mileage, projectors (i think) and much more on both of these cars.
bottom line though, i wouldnt look into the pros of both cars, but into the cons about them. look into what upgrades you would like to do in the future. you cant put a big stereo into that convertable s2k like you can in the wrx.