Hi, what kind of screen protector PSP SLIM user uses?

I ordered Capdase and Hori from Play asia and both can't apply perfectly. There are bubble gaps on the four edges of the screen. I have tried more than 4 types of SP. My PSP-1000 doesnt have that problem. Is it because the LITE screen is uneven at the edges?

PSP SLIM users are welcome to share their view.