Is your boat named Go For Broke? I think you have my old 31SS. If it is my old boat, your props are labbed bravo 1's, done by Throttle up last winter. They are the best props you will find for it. Mirage Plus may get slightly better top end (1-2 mph) but at a huge loss of rough water handling. If you want to try them get 23" or labbed 25", but borrow them don't buy them, you won't like the way it feels.
By the way, thats the nicest 31 you will ever find used. I used only Mobil1 15w50 in the motors. I always used 3m ultra performance wax and 3m vinyl treatment/cleaner. Good luck with her!