I've been real curious about this. Parts vendors have always sold them for 7.62 AKs, but I've never heard of anyone needing to use it. With my own somewhat limited - but still 12-year experience firing AKs, I've never had a broken shell in the chamber with ANY ammo from cheap to commercial Russian 4 types, Yugo, S African, Chinese 2 types, and American 4 types SAAMI spec.

Is it even worth the $8 to have one for 'just in case' ?

I have one, though I've never had to use it, but I have one for just about every one of the caliber
types that I own.

I figure, if I need it, I have it, and it's only $8 bucks or so. I've wasted more on other crap that I
have nothing to show for it. Besides, if a case would separate on you, and you didn't have one, a
smith will probably charge you a lot more than that to extract it for you.

good question!

i've shot literally thousands and thousands of rounds of cheap Chinese, Russian, com-bloc steel and brass surplus through SKS's AK's and Mosins without ever having the need for one.
. . .i just saw one for $3
i guess it pays to have back-up when at the range.  .   . if you see a Mosin or SKS for $75, BUY TWO OF EM!!

I would have given a testicle for a ruptured case extractor in Iraq.

Iraqi ammo sucks.. lots of case head separations.