bikeaddiction1

I have a Martin Backpacker, and while your observations have merit it does have some big benefits. It is 36" long which does mean you need to stick it out the back (not so far as to need a red flag) or mount vertically on the side, but it is very slim so you do not have to deal with the bulky volume and wind resistance of a folding guitar. I think it would be easier to damage a larger guitar in a spill, should that happen. It fits very well inside readily available kayak tapered dry bags so it is easy to waterproof. I have taken it on many canoe trips. When flying it is easy to carry and fit in overhead bins without taking up hardly any space. I have had people ask if I am carrying squash racquets.
I live in a dry climate in Alberta and have taken it to Alaska, Costa Rica, and Hawaii and multiple river paddling trips and have not had any temperature or moisture issues, although I don't play it in the rain. I also find that for it size it has good projection and sound.
The playing experience is different and it took some getting used too at first. As I only play it when I am traveling I do need to play for a little to get used to it again if it has been awhile, but once I am comfortable again I forget about it. This to me is it's only real downfall and I much prefer playing a full size guitar, but if I had to bring a bulkier 3/4 sized or folding guitar on some of these trips I would find it to be a hassle and would likely not bring one at all to many places I have taken the backpacker.
I have not taken it on a bike trip yet but plan to this coming summer, so I will see if my opinion changes.