Hey tanky people!

New and aspiring tank here with a basic question. Is there a common opinion on strength vs rate for shields? I see that a lot of the shields favor one or the other fairly heavily.

I've been using the more "rate" favored shields as consistent block seems better than more random larger blocks, this however is based completely on my own logic and may have no real truth in the game. Also having just hit level 30 the more I block the more I can use that shield skill who's name I, embarrassingly, can't remember now.