Waiting on my sdn-6, for a similar purpose (300 blk, 10.3" barrel). But with the sig brace fiasco I'm going to sbr my pistol. Been waiting for my stamp since the end of November so in a month or 2 I can tell you about it...
Not sure if you really need to take it apart. I've heard that with a .22 can where it gets dirty fast it makes sense. Otherwise, don't worry.
And I found mine on sale and with the stamp it was just over $1100