Thinking about the internals a little more, especially in relation to the pistons, I can remember thinking back at the respective times and how disappointed I felt with the Mercury S. I did have an early Mercury back in my teens and also remember that not impressing at the time. With the Mercury S being the flagship break barrel for BSA at the time and attracting many fans even now, I expected better.

The Supersport, on the other hand, impressed with the quality of, and finish to, the piston.