My choices haven't changed since the last time this magazine question was asked.
I get Dive Training, Rodales, Alert Diver and Undercurrent for many of the reasons stated in the preceding posts. If I had to do with just one, it would be Dive Training.
The two I dropped were Sport Diver and Skin Diver 'cause their content has degenerated to little more than pretty pics and puff travel articles. Too bad. Skin Diver used to be a pretty good dive pub back in mid 70s-early 80s.
However, sometimes when there isn't any diving to be had, reading those two is better than nothing...but not much.
Warren