In my experience, the Dark Silver Shield is simply the best choice for PvP. The low weight, 100/100/70 damage reduction, ability to parry, built in magic defense, and usable hit resistance give it huge advantages over other shields. Many of the other viable shields have high strength requirements, have a fairly useless shield bash instead of a parry, or simply cant deal with magic based attacks. I upgraded a Knight's Shield to +10 and find it does well — when there's no magic around, and in PvP you can bet your life that there's going to be some magic damage. Excluding non-blocking utility shields like the Adjudicitor's, why would anyone apart from pure turtles use anything else? (Oblivion players will get my allusion, lol, couldn't resist ; ) )
Couldn't find a bunny with toast, ah well.
PSN: toasT_Bacon, toasTBacon