Hello Tiancen, The pundits often suggest keeping the selenium reduced (and indeed, it's not a bad idea) however if you're worried about disulphides - I would say that they take precedence over the selenium. If you work reasonably fast you should be able to have the best of both worlds - have the selenium safe and the disulphides oxidized.
Not to mention that there always are the good old heavy atom derivatives to fall back on if the selenium data does not pan out :) Artem
