Just curious, how far do those setups cast on grass off the water? It sounds like I am getting as much or more out of 11ft rods which coincidentally take the same grain ranges but are rated more in accordance to overhead lines (11ft 11/12wt, 11ft 9/10wt).
Having tested a broad range of rods on the beach since 1995, I find 11ft considerably more useful than 13ft for overall fishing (IMHO), but the longer rods have the potential to deliver greater casting distance due to a potentially longer stroke length and path of acceleration. The question is where the point of diminishing returns lies. Again I find it to be ~11ft.
At 380 grains the 5wt 12fter is actually a 10wt in AFTMA terms. At 650-700 grains the 9wt rod is probably off the chart by AFTMA standards (15-16wt?) as well although 12-13wt overhead lines available commercially typically fall close to that range in grains.
So both of these rods must be rated by spey line vernacular, emphasizing the huge difference between overhead lines and spey line ratings!
How about the stripping basket - which one do you use?