https://docs.google.com/spreadsheet/ccc?key=0Ahq83z2FEBm5dFVhN1dvTWZyN1lZMGltVXcxMDRGLXc#gid=0
Shinano - max speed 39
Enhanced lvl110 20" twin equivalant(crazy damage per shell and BEST spread)
also lvl 100 18.9" tripple available but you should use 20"twin. its the best.
Weaker structural strength
7 support slots
mikawa can mount the same guns as shinano and also has 2 more support slots, I think more people prefer the shinano though, Im sure someone who has both can tell you more.