Lock up is very good on the Byrds. Steel on the Byrds is also very solid. Should be not too different from AUS-8. To say which one is better seems a moot point to me. If treated well, both should be very comparable. You could argue that the added V in the Byrd steel adds to grain refinement etc. but really, I think bottom line is that you won't be able to tell the difference. The thing though is, that the Byrds seem to be treated very well, while AUS-8 seems to get less then stellar reviews here and there, I would assume because, of a batch of bad or too soft heattreat (just a guess though). The Byrds are run pretty hard at 60-61 Rc, which seems to perform very well. With Boker I wouldn't worry too much though.
Again, between the Cara Cara and the Trance you are in the lucky position of not being able to go really wrong. But I hope you realize that these two are quite different in size. The Cara Cara is by most standards a fairly large (long) knife while the Trance, like most (all) of Chad's designs, are fairly small and compact.