I found a sup eth zak shield

317 base defense
114 attack rating
9% enhanced defence
53% enhanced damage

Would anyone use this if it was an exile or is it basically Vortex or nothing?

bad base. and fewer people use exile against barbs n druids these days, so eth res bases are easier to sell. vortex is also a generally awful base since you can't cube soc for bugged def anymore.

ST and SR are better and as far as knight's mod bases go, don't bother unless it's at least 60 ed