Hi Mara, We have 10 cellwashers of Sorvall and 5 cellwasher Helmer. We have been using Helmer since last year and half. They are CRAP. In 60% of cases we have problem with Check Cells not working. In 80% of cases the numbers on the tube get wiped out after a 4 cycle wash. Sorvall are comparatively good. We are a facility which processes approximately more than 100,000 samples a year.