Further, if I remember playing enough rounds, almost all my remaining measure will be in the B world, and so I should play, imitating the simple bayesian answer. UDT-like approaches reason that in the A world, you want to never play, and in the B world you want to always play. SSA, because that one me is also 100% of my reference class. SIA, because theres one of me in both worlds. Neither Self Indication Assumption nor Self Selection Assumption update this any further. So if I played often enough, I will have updated to mostly believing B. Now A has a lot more prior probability, but the likelihood ratio is 5:6 for every time I played.

B says that everyone else has a 1/6 chance of dying, but I survive for sure. Consider two hypothesis: A says that everyone has a 1/6 chance of dying. It seems to me that the answer is no, but existing formal theories disagree. You also remember many other people doing this many times, and dying about 1/6th of the time. You remember doing this many times, and surviving each time. You are offered $1 for spinning the barrel, pointing at your head, and pulling the trigger. Surprisingly, our current theories of anthropics don't seem to cover this.

Best way to play russian roulette