People trying to slide one over with carry on that's clearly too large/heavy is a pet peeve of mine, disruptive. Last flight a nimwit actually started moving other people's things, without asking, between bins, because he was carrying this gigundo "carry on".
Flight attendants had a few really firm words with him, carted his luggage away.
Personally, too much of a hassle to bother -- my Aeris Reefrider is a small, travel, BC, but still too large to be worth trying to squeeze as carry-on, particular if flights might include some smaller aircraft. BC, fins, wetsuit go checked, along with my pony.
I use a nondescript daypack to hold my regs, computer, camera, mask, that is my carry-on.
Flight attendants had a few really firm words with him, carted his luggage away.
Personally, too much of a hassle to bother -- my Aeris Reefrider is a small, travel, BC, but still too large to be worth trying to squeeze as carry-on, particular if flights might include some smaller aircraft. BC, fins, wetsuit go checked, along with my pony.
I use a nondescript daypack to hold my regs, computer, camera, mask, that is my carry-on.