After watching several glowing reviews on youtube, I decided to take the plunge with a six string set of Ernie Ball slinky cobalt, and hang the expense... The sheer tone improvement and longevity were more than worth the money. I was delighted when EB saw sense and introduced a seven string set! Not only do they deliver excellent tone and staying power, the gauge selections in this set are very well balanced, with a mighty 62 on the seventh string. I had previously been compelled to change strings after only a couple of recording sessions to preserve the sustain and clarity... with cobalts I am five songs in and they are still bright and powerful. Now, I wonder when they'll introduce an eight string set... Many thanks Ernie Ball!