Has anyone used it? Kaz Fighter is apparently free and the newest update is similar speed to perfecticus's fighter. Im going to have a look at it on RSCA because if its free, whats the point of paying for my perf fighter?

Generally paid bot's will be better the free bots.

It's better than a paid bot, and it runs on the same base.
There is no point in paying for Perf's fighter if you have Pro when Kaz fighter is so good (from what I hear from members and Kaz).
However, if you don't have a pro subscription (which 99% of people on Sythe don't) then Kaz fighter is not available to you.

Its amazing. I tried this and managed to get 75k/h xp.

Paid Bots > Free Bots

how do you get a subscription with kaz?

You have to purchase iBot Pro from rscheata.net ($60/year), which lets you use the rsbots.net client with 1000+ scripts (most of which are better than the ones rsbots.net has).

Btw, Kaz Fighter is in KBot.

The ported version is on kbot. That is barely worked on compared to the version at RSCA