I’ve been impressed with elektron support.
I went through a long phase of my OT mk1 having occasional audio issues. I eventually sent it in, and as would be the case for me from time to time, the error didn’t show up. Elektron sent it back. Problem recurred, sent it back in again.
Long story short, outside of warranty as this process took so long, elektron eventually provided me with a new Mk1 (maybe the last ever unit as Mk2 had been launched).
Still, it was a good approach as I got a new machine and it was 3.5 years post purchase and they acknowledged the error was long standing but erratic.
On several other minor matters they have been very helpful and courteous, so based on my experience I still see their support standard as very high.
I’d be more critical of their selection of components from time to time (RYTM 1 LCD for example) for machines we buy to last for decades, but that is a design dept issue not support.