I just wanted to get your opinion on this.
I'm playing a Javazon with Infitiy merc but there are still some light immunes.
They are not that common and the merc can kill them so do you think a lightning sunder is worth it?

Sunders are what, 10fg now

Doesn't hurt to try

yes, it makes a big difference. it means you're able to kill light immunes before conviction kicks in, which speeds up your clears noticeably

I can second that My javazon has both and she just tears through p8 games like no other.

Because D2 PvM was super hard that we needed these sunder charms right?

I see nothing appealing about D2R... is it just me?

I don’t think it’s necessary but it does increase your clear speed to a noticeable level