I had a Riken which died just before the 2 year warranty expired. Quarq replaced the spider with another Riken unit. That died 18 months later, but Quarq replaced it under warranty. Then it got stolen because @Cycliste left my rather nice road bike unlocked in a communal bike store in her block of flats for local enough for it to be nicked.
tl;dr they're not as reliable as P2M but the customer service is good.
You can keep your P2M reliability and eliminate the flaky Rotor spider mount by getting SRAM cranks (e.g. Force 22 comes in 165mm BB30) and the matching P2M power unit.
I had a Riken which died just before the 2 year warranty expired. Quarq replaced the spider with another Riken unit. That died 18 months later, but Quarq replaced it under warranty. Then it got stolen because @Cycliste left my rather nice road bike unlocked in a communal bike store in her block of flats for local enough for it to be nicked.
tl;dr they're not as reliable as P2M but the customer service is good.