I was struck by the very short piece you mentioned. I usually carry a light climbing rope when in rough country,even when the plan calls for sticking to the trail. But I would carry a minimum of sixty feet, and one hundred feet is often preferable. At a diameter of 8 or 9 millimeters, the weight is tolerable. This strategy has paid off several times for me.

One more suggestion. Do you contemplate any overnight trips? If so, I feel it would be preferable to invest in a quality sleeping bag, and/or tent, or conceivably, upgrade your backpack. I would put any of those items at a higher priority than either a PLB or GPS. In the Superstitions or most of the country in Arizona or similar environs, you will do very well with quality maps and terrain association.

I would agree with Russ with respect to the Garmin 301, which is the model I use. But I would put either electronic appliance at a lower priority than acquiring a good, basic set of backcountry gear, and acquiring substantial first aid training.