Absorber?  front or back side? is it make sound like rusty metal spring?

Maybe it's the brake pads. It may also be a problem with the servo, or it's just that you have to press harder on the brake pedal once it becomes stiff according to others who also use the Evo servo.

For mine it's certainly a big step up from the previous servo. I think you're still not used to having to press hard on the brake pedal to get the braking power you want.

I'm not sure about this. You can try asking your mechanic to see what can be done, or maybe contact Zordaq Motorsport/Engineering for their opinion. What brake pads are you currently using? Did your mechanic bleed your brakes for you after the installation?

When I got the servo installed, it wasn't as good as I imagined it would be at first cause the car didn't seem to be stopping fast unless I pushed harder on the brake pedal once it becomes stiff. Now I think I'm used to the brake pedal feel since I have no problems so far with stopping my car fast.

Did your mechanic bleed your brakes for you after the installation?

After installation the servo, your mechanic should remove any air introduced to the braking lines/system during installation by pumping fresh brake fluid through the system and out of all the bleeder valves located on each of the brake calipers. It's normally done by having one person pump the brake pedal, while the other person deals with the job of opening and closing the bleeder valve to let brake fluid out until there is no sign of air bubbles in the fluid that comes out.

Are you using original Proton brake pads? I heard that their braking power is lousy.

Then I think you should upgrade your brake pads.

How much it cost? been thinking for it so long, stock brake power quite weak...

Maybe try some other brand or more expensive Bendix pads like the Bendix Ultimate. My Bendix MKT brake pads make a lot of groaning noise when they're cold and the car is almost at a halt even when they were still new.

Not sure. Can try enquiring. Why don't you consider other pads like Rapid stop or EBC brake pads? A forumer called Kent Goh @ xd auto parts should be selling them I think.

Recently I just changed my front anti roll bar bush at shop.
Cornering now is good , lotus handling is back. before changed the bush, during cornering you can slightly feel that the car have a bit shake, feel also not sharp.

After that , I self changing the rear anti roll bar bush and front absorber link.
Now the cornering power better, back to top performance when getting the car, even using lousy tyre haha

The Persona comes with a front and rear ARB by default.

http://speed.academy/how-swaybars-work/

My car front is original anti roll bar. Even though is ori but still have it function there.

Rear I've changed to 16mm Ultra racing anti roll bar. Cornering better than original .
Both of the original anti roll bar quite "soft" if u put some strength on it, it can bend a bit. But UR totally no strength to bend it. Damn stiff.

I got a rear 16mm too. To be honest I don't feel much difference.

I got a rear 16mm too. To be honest I don't feel much difference.

1. Better brake pads
2. Better tyres

Then move on to whatever you want.

Upgrading car's performance can be put into three broad categories. Engine performance, handling, and stopping power. If one of them raises significantly, you will need the others to be upgraded as well to balance out the car.

surprisingly stock H-Line brake servo is not bad..no need to change double layer = save money 

nope..SV servo similar to saga..weaker