My favourite is Tactical Knives hands down. The reason why I like it over the others is because of the "real life" reviews of knives, self-defence articles and tips on knife care. I only wish the issues went out monthly.
Blade is okay, but I find most of their issues replete with what the latest trends are and not enough reviews on how the knives perform. While it's nice to see company/knifemaker profiles; Best buys under $100; New knife releases and all, I'd like to see more honest reviews on how the knives featured actually perform.
I'll pick up an issue of Knives Illustrated here and there if it has an interesting article. Again, not enough real life reviews and it's too "artsy" for my taste.