I have been using DR Hi-Beam stainless steel strings for many years with no corrosion issue. For example, I have a set on my 06 Jazz Bass that have been installed since January 2008 and they STILL show no sign of corrosion, AND they sound fantastic. I have had similar experiences with several of my other basses. That said, the last few sets of Hi-Beams I have installed are showing major corrosion (or dark places) following weeks to months of use. This appears to only be happening with sets I have purchased recently. I keep my hands as clean as possible and always clean the strings with Fast Fret and a wipe down following a session. Has anyone noticed a similar problem with DR Hi-Beams? Has the formula changed? Is DR doing this intentionally to push coated strings?