I still think OB would be closer akin to Skyrim than FO3.
ps - how do you abbreviate Skyrim anyway? SK, SM, SYM, ...
SK, I have seen others use SR (and that makes sense in the context of how the word breaks down, but for some reason it makes me think SI ) but I prefer using the sound of the first two letters.
Read the OP and then youll understand
??? I did read, and that was my response. I am sorry if you don't like my answer but that was the only way I can think of that FO3 can prepare you for SK