Plenty of comments about them if you search, but general consensus is "they're brake pads" Nothing special about them, but nothing wrong either.
I think if you're buying mid-price pads, there's very little between any of them. A well set up brake has far more impact than pad quality

 

Thanks.
I did indeed do some searching and, surprisingly to me, found not a single mention of them. [Maybe I need some search tutoring.] I'll try again.

 

I found quite a lot of info about them here

 

Gorilla pro semi metallic is the best brake pad i have used i have been on 1 trip to the alps and loads of riding in the lakes and im still on the same set using magura mt7 never failed not even on long descents

 

I've only ridden them with Shimano brakes, pretty neutral, not bad and not great.
In recent years, Sram Code RSC and Galfer pads. In the Alps I use Trickstuff 840 pads.

 

I’ve used their multi compound pads on 2-pots with resin only rotors as an upgrade over standard and they had more power, better bite and ran very quiet.

mum just in the process of upgrading to Deore 4pots (have the brakes and have just revived the rotors in the Mail) and am now debating to go with Gorilla sintered pads Or go multi compound again.

I would highly recommend them over shimano’s own resin pads. Sintered I could not say, but generally I trust brands that I know and have used and I’ve been very impressed with them based on my current experience