Probably the most local to me... went last week in need of some rodi water asap. Got 15g and brought it home only to find out the sg was at 1.011 --- I could have brought the refractometer to check it but never thought of it. I asked and they told me it was about 1.023 so I knew I'd have to adjust slightly. This just goes down my list of less than stellar experiences, lesson learned.