how do the stock brake pads perform compared to shimano ones?(k05s / l05a)

So far I am running both the Juintech F1's and the BR-005 with the original pads that came on delivery.
I am also wondering what improvements could be achieved experimenting with different pads...
Hopefully somebody can share some experience with different break pads and make some recommendations.

BR Chris

Could you give the BR-005 a test already? Could you leave some impressions?
I'm in the planning phase of my CFR696 build and those are the brakes I'm likely going to use. Though I'm a little bit concerned that I'm not going to be that happy with the brake power. (coming from V-Brakes with compression less housings on my old-school graveler.. but I also have 4 piston brakes on my all mountain fully, so I'm kinda spoiled)

You could try semi-metallic pads? they're certainly more abrasive that the stock resin ones. However I remember Juin support explicitly telling me to only use resin pads with the GT-F

It's a bummer Onirii didn't design the BR-05 for finned pads though. K03S is just the non-finned version of L03A which would open up a lot of cool stuff like SwissStop's EXOTherm2 or Jagwire's Elite Cooling. If you want to keep things resin and OEM, I guess you could try the K05S which is the latest in the Shimano K02S/K03S non-finned resin lineage.

That's quite a good hint with the K05S, since K03S seem to be out of stock atm pretty much everywhere where I look.
Sorry for asking and kinda hijacking but the B03S would likely not fit, right? (besides they are using a splint and not a screw to secure the pads)
While I'm at it.. regarding rotor choice: there are shimano rotors designed for wide pads (as B03S) and narrow (like K03S) pad shapes. Would I experience down sides using rotors designed for wide pads but actually using narrow pads? (the other way around would make sense to me to be disadvantageous)