sprk1lot's of modding you can do to the Sumo.
Harold is THE best Seiko modder around,but
Google modded seiko sumo & it will take you to WUS w/ plenty of examples of mods you can achieve w/ the Sumo
sprk1Yobokies has a few bezel inserts, a sapphire crystal, a number of bracelets with end links made specifically for that case, as well as being to fit any of the dials made for a 4:00 crown, and of course hands. Dagaz also has a sapphire, and a huge selection of hands and dial.
I bought 2 of these watches, one will be modded, maybe both . :)