deano,
if you keep around the 6m plate mark the suzi should be fine.
my 6m goldstar runs fine with the 140 suzi. 150 / 175 would be nicer, but most days i am running around 24 - 27MPH cruise, which is about all the seas will let you do on an average day. the suzi is running 4600 - 4800 for this.
hope this helps.
BTW goldstars are good things for your research list.
steve