Reliable as in failure rate is lower than other brands.  DOA rate is also quite low from what I saw.  Hard to put a percentage on it as I never kept a list but out of box DOA was probably 1-2 out of 100, and failure within a year ranged, I'd say 3-7 out of 100.  Not all failures were a result of the manufacturing, not everyone was as *ahem* skilled at building water cooled systems as others.