I've really enjoyed the more in-depth articles on nutrition and training by Ferguson in Grappling lately. The overall quality of that mag has increased over the past 2 or 3 months, I think.
I like Couture's articles in Bodyguard, usually. I also like all the techniques in the middle of BG each month. But it's bi-monthly, and that makes its coverage of events like UFC and Pride even more dated than Grappling's.
I can't say that either mag really brings anything unique to their coverage of those events. I do, however, appreciate the coverage of the smaller fight orgs, mostly because I'm too lazy to keep up with them myself online. :/
I keep all my back issues of each, though. Re-read them often. I've especially liked going back and reading up on these folks showing up on the Ultimate Fighter or new to UFC/Pride who had been covered in Grappling years earlier, I just hadn't paid attention. But I'm still learning.
I've not read enough of the other mags to really have a solid opinion.
I'd subscribe to Grappling, but have heard nothing positive about their service.