I had a subscription to "First Class Flyer" a number of years ago and found it to be mostly worthless and certainly not worth the price. I did not renew.

Most of the articles are about Business Class (not First as the title claims), they contain virtually nothing that you don't already know, and there were always 'teasers' for next month's exciting issue which sounded interesting but never seemed to materialize.

Flyer Talk is a vastly superior (and free!) source for travel information.