Archie - I do keep width and color of mag strips as well as color variations on the front for my collection. The manufacturer would apply the mag strip (same width and color) to an entire order which may vary from the next order even though the front design doesn't change. Does the casino specify to the key manufacturer the width of the mag strip and/or color? Or does the manufacturer just apply whatever they have in their machines that day? I may be wrong, but my guess is that the casino doesn't care about the color or width of the mag strip unless the mag strip is too narrow and won't work, then they would start specifying a minimum width.

Whether or not you'd consider these as "variations" that all collectors try to add to their collections or not, I would agree with you - they would not be considered "variations". It would be more of a personal issue. And at the point where we say it's time to start downsizing to make room for more current keys, those types of differences that we keep would be the first to go.

The variations I'm finding in these RRs have been with the older Reno Hilton keys which has been a nice treat. The dupe in this one RR was a Palms Bacardi Global Gathering red key - I looked it over carefully and didn't see any variation (and they were on different pages). I thought there was another dupe on the Plaza keys but could see the variation on the backs (and they were together on the same page). So we all did very well with eliminating dupes on these RRs.

That's my 2 cents worth.

Esther