@bloodangel broadly, Sindome had core code from Cybersphere, if I recall. Sindome is far and away different than CS is, now
I prefer CS, because I feel like I can make a decent character now, instead of being utterly shit for forever on Sindome. The RP on both have been great for me over the years. Just... Far less on CS because it's a small player base game now.
What CS gas going for it over Sindome, in my opinion, is a fleshed out Matrix.