I find used iriz 1.6mt premium 2016 for 25k.its a good deal?.

Thanks for the information.

I think I will only go with coaxial speakers because I don't want 2 tweeters on my dashboard, and a subwoofer is too much.

I'm not looking for like next level sound quality, I just some something less flat. Stock speakers on Iriz is really potong stim. 

I have my eyes on this
https://www.edifier.com/my/en/car-audio/g65...nt-car-speakers

But not sure if the speakers fit on Iriz or it needs some modification on HU.

Add:

How do I check the maximum output for Proton Iriz HU?

Truly PnP need 6" speaker set. Unfortunately it's unpopular size so rarer to find major brands carry this option. I've seen pioneer to have it but no extensive line ups choice to pick like common 6.5".

Local brand like Mohawk do have one marketed especially for iriz.
But 0.25~0.5" difference is not that much to have to resort to cut a hole... I know as I myself use 6.5", they only use plastic spacer then drill new screws few mm's apart.

Truly PnP need 6" speaker set. Unfortunately it's unpopular size so rarer to find major brands carry this option. I've seen pioneer to have it but no extensive line ups choice to pick like common 6.5".

Local brand like Mohawk do have one marketed especially for iriz.
But 0.25~0.5" difference is not that much to have to resort to cut a hole... I know as I myself use 6.5", they only use plastic spacer then drill new screws few mm's apart.

This 1 right Mohawk Iriz ?

Still need to drill if buy those speaker? My current stock speaker sometime will sound high sometime will low again 
Will it solve that issue if i install this speaker or need to change Head unit? Mine is 1.6 cvt exec

Oh I did not check the dimension (sorry can't help with that) but my 6.5" is average entry level set, not some SPL-grade with obvious oversized magnets. The installer have no problem with fitting it, only need spacer to bring the unit a bit forward for magnet clearance. No cutting anything done as I observed the whole process.

Front: 6.5", Rear stock 6" ....Not much difference isn't it?

This not so sure where they actually made it with 6" or 6.5" with adapter accessories included then simply slap it with car model sticker in hoping the installer know what to do  Try to confirm with the seller first or do some research from user reviews.

Change speaker only? Or do radio also?
Usually if change speaker the cut the end of the stock connection near speaker.

Probably bad ground on the connections they made..

Changed head unit and speaker.
But headunit I made a point not to tap original wire, so they found a socket for the wiring.
But when change speaker, I notice they tapped 2 wires before a socket near the bottom of A-pillar.
What I meant is, where a bunch of wire connecting into a socket, they cut 2 wires out of that bunch and tapped the wires.

Stock doing great for me so far at sepang trackday.
RM300 from sc
I'm thinking to have others better options for the amount i paid

Maybe. Any other manual owner can test?

to those who are wondering how it looks behind the door panel