It just depends on my observing goals.
If I am going for a causal hike in the woods, then light weight bino are taken,
if looking at shore birds or distant raptors, then bigger binoculars;
but all optics are chosen with some degree of bondings or fit.
I have about a dozen pair. Of those the 8.5x42s are the best all around pair,
but each of the others are better for their nitch in observing--"the right tool for the job"
an example--I was excited when the Nikon WXs came out-these were clearly the best quality binoculars available,
but even if I could have afforded them, the weight and cost made them noncompetitive with what I have.
edj