I'd agree with bagsieblue on the old 90s guitar magazines. I have a few (Guitar Player I think) and they have pages and pages of transcriptions, as well as interviews. There is an interesting interview with Eddie Van Halen and Nuno Bettencourt at the same time; also I think one has the Star Trek theme transcribed from Stu Hamm, plus I recall an interesting interview with Tom Hamilton of Aerosmith. Some real insights in all of them, as they were free interviews not questionnaires.
I have a bunch of old Bassist magazines (yes I have the 1994 edition with the CD, there's some dreadful tracks on there interesting though it is) and all the early BGM issues that I am working my way through. There are some interesting articles in there but even though that old and perhaps in the "golden" years of the magazine it doesn't feel like Sound on Sound or some of the Bassist articles. Transcriptions are always interesting.
Reviews of gear is fairly interesting but it isn't my main concern, as I'd have to spend more money! It looks like a balance is to be had (some people complain they don't like all the expensive boutique basses reviewed) yet some want to be informed of gear they don't know about (which would include all the boutique basses, right?). Tricky!