I'm not surprised. l was playing a lot of AC/DC, channeling Angus several hours a night - I self tought myself rock guitar 1980-1983 - and the strings did stay in tune, and sounded killer, prob because of some hot new alloy, beyond steel/nickel, so I used nothing but that brand forever, and then eventually reverted to using Slinkies because of the price 3 for $10 when I got more into guitar peddling, and then eventully back to Boomers, my original strings from the 70's, and nowadays I'm using primarily GHS.