interesting to note that #455 was a transition boat and does have the 500 series deck but the original interior.
Having owned two 500 series, and a 300 series ... the combination of the earlier interior and later deck would be my choice to look at.
most of the stoves in the 500 series were overkill, the buried access to the motor a pain in the ass; the batteries require an gorilla to move, or check; and the port cockpit storage is a back breaker. I don't know when they flipped over from the 3/4 to 1 in. shaft, but that would also be something to look at.
however 505 is not for sale for at least another 4 years.