I have the Otto book (the small one) and also the Washington echo manual but rarely used them. Lots of time during echo rotation i find it faster to just google whatever I don’t understand or need a picture/video examples.
So yeah, Mayo video and Klein would get you 90-95% of all you need
For reference I think Oh is an easier read I loved it when I started fellowship. In my third year I switched to Feigenbaum because it actually was more solid.
You can’t go wrong with either.
However for boards Klein and lots of questions and some Mayo videos