Thanks for all the replies. It's very valuable for my decision. Parts are available at PacParts (which is not ideal, being European), but I don't know if I will just get a new bezel, back cover and resin or the whole shebang (sensor cap, buttons, case+glass). I'll wear it like this for now, I think it's fitting for a Master to be beaten up.
As it is Friday night, I had some kebab with friends at a Turkish "snack bar". And I cleaned the Riseman after I came home. Good thing I did it in that order, because I lost all appetite after cleaning the watch...
Warning: Gore images below
The only tool you need for this job
Nice that I don't have to fumble with spring-bars.
Yuck yuck yuck
This picture at full resolution will make you puke. Yes, that's a hair stuck in there.
Everything taking a bath
After a rinse, bath, another rinse and some toothbrush action. There is still grime near the edges of the glass, but I can't seem to get this clean.
All clean, very nice
This watch features a "win sensor". It measures the amount of win.
Bottom looks almost brand new
Top is pretty much the same
There was still some grime near the "ALTI" text on the right and also above the "RESET" text
A bit of toothbrush action and it was gone
It's a nice design, the resin back cover. Too bad it's such a dirt collector.
Thanks to member ivt for the extensive tutorial on dismantling a GW-9200. Especially the part about the O-ring. Very useful.