I didn't know it was possible for domestic use, but my stock burrs died. I just couldn't grind fine enough anymore for espresso.

Upgrading to SSP burrs was a breeze, the hardest part was the cleanup. I'm lucky to have a pretty well aligned grinder so a single shim was necessary.

The difference with the old burrs is amazing despite having barely seasoned these burrs. A lot more range is available (I'm currently grinding pretty fine at +21, while the old burrs in their prime only had around +5 to +12 of usable range). Going down to +15 is enough to choke the machine. They're a bit slower than the old ones and have a much higher pitched sound.

HU burrs are all about texture. And oh boy the espresso they create is syrupy as fuck. Taste is great too, they bring out a lot of different notes from my beans. Maybe not extreme-clarity, but still as least as good as the old ones without compromising on texture.

All in all, I'm pretty happy with the upgrade.