Hi everyone. Do you think I would gain an advantage if I buy 2 SB-105 strobes instead of 1 DS-160? I know that the 105 is manual only on an ikelite housing for a DSLR--I wouldn't mind manual flash. But is TTL really that much of an advantage underwater? Also I'm considering the power output, my lens is a Nikon 16-35 VR if that helps. Need your thoughts on this. Thanks