We have used for well over a year, and like the Quotient ABORh very much. They do react a bit different than our past antisera, but once you get used to it they work very well - particularly the Rhs. The price is just SOOOO much better. I haven't seen the same problem with buffered saline (we don't use the cubes), and I just checked one of the PIs, and I couldn't find the requirement to use unbuffered. Are you in Canada too? Is it possible the reagents are different there?