Our personal preferences for boots vary widely, and with that the rigidity of the boot itself. Some boots have a full shank, others half, some quarter, and some almost none. Some boots have little torsional flexibility, others you can twist almost like a pretzel.
Personally, I like a full-shank boot, with little torsional flexibility. They protect my toes and ankles best - I can roam all day in the Northern Presis, easily finding a foothold on sharp rocks without concern of feeling the rock thru the sole. And on a long hike the soles of my feet don't ache. So, any footbed like Superfeet are redundant - the boot already provides that support so additional support makes it feel like I'm wearing plastic mountaineering boots. Sometimes the factory footbed is adequate, sometimes I prefer one with a bit more cushioning, or simply need to change to a thicker (or thinner) footbed to made the boot fit better. When ready to retire a pair of boots, I check the condition of the old footbed - sometimes they have enough life left in them to salvage. Over the years I've watched for sales at EMS/REI/STP for footbeds made by Merrill and Vasque, and between that and saved footbeds, have a 2-gallon Ziplock bag of spares that I have in reserve. Boots change - shrink or stretch, and depending upon the season my feet may either swell (in the heat) or shink (in the cold) so I swap insoles in and out.
Hiking/mountaineering is a big part of my life, and taking care of my feet is a priority. My feet like it when better when I rotate different boots on a regular basis, rather than using only one pair during a particular season. The exception is winter, when I wear STP's Avalanche nearly exclusively.
