Hey Brett, IMO that recupped 17" Solas will be lucky to pick up 200 rpm @ wot.. You want to be getting at least 5500rpm with your usual full load, (not in a empty boat),, thats why I suggested a 15" in the Rebel or the Cyclone..
The standard SS, if like the SST or Viper, when swapping to a Rebel or Cyclone you need to drop 2" in pitch to maintain same wot rpm, IE, 20" SST will have same rpm as a 18" Rebel or Cyclone. However you need to increase your wot rpms to 5800 for a light load. 600rpm increase... Each 2" is equal to 150-180rpm.. So if your prop is like the Viper or SST the 15" Rebel will spin to approx 5800rpm with a light load.. That is the experience I have had testing Vipers, Rebels and Cyclones back to back on a Seafarer hull.... And IMHO the SST and Viper is garbage on the Seafarer hull unless you only want to travel flat out... The Rebel and Cyclone are by for superior for offshore, choppy rough water, slow speed planing and economical cruising..