Enjoy.... That nice thing is there to stay and not like KYC which you only have do once (if there is no changes on account which need to be verified), but this funny thingie can be ongoing that you might to do it time to time that operators have up to date information about your SOW when you keep playing and your cumulative amounts of deposits keep increasing... Hopefully there would be relatively soonish some bit clearer guide lines for operators like KYC is pretty much standard process and all follow same practice, with SOW it seems that there are not at least yet really clear guide lines and common practice which all operators more or less would follow same way, now there are quite huge differences in different operators SOW policies (some MGA licensed casinos don't really even ask them yet, if there are no really high risk categorized players).
When reading experiences about these processes, there is quite a lot place for improvements for better user experience, getting more clear guide lines when request and what would help casinos to make process easier, now it can be really exhausting and like somebody mentioned, start to be easier in some cases get mortgage from bank than get your SOW/SOF approved.....