I finally got to take my Hasselblad 500ELX for a high altitude spin this morning on a Kenyon KS-6 gyro, shot at 14-16,000 feet, Tmax-400. My wife helped me keep track of A12 backs, I brought 5 and used them all, three re-loads plus a couple rolls of 35mm in my F100 for super long shots.
I used a pair of "Hassel-Converter" 9V battery packs and it simply rocked! I was going through a roll of film per pass on targets that used to net me at most 3 shots hand wound on my 501CM. Paired with either my 100 or 180 CF, this was a super productive flight.
Damn I love this system!