Does anyone know if this is a good skill to increase?

This skill seems to be great (start off skill). Assuming the monster didn't have aggressive on you already. At Lvl10, it does 300% times physical damage. That should saves about 3 or 4 seconds of skill spamming or regular attack.

I hear a lot of people say that this skill is not good. There has to be a reason behind this. Can I hear some opinions please?

I'm planning to PvE most of the time and I don't know if this skill is worth putting into.

save you 3-4 secs of skill spamming? it depends. my ordinary damage deals an ave of 4k while my lvl 10 aim around 5-6k only. yep max it if you want to go to heaven hehe.