Log what ever you want as PIC, but FedEx, UPS, Southwest, and Expat Jobs, that require xxxx hours of turbine PIC, only accept one kind - real PIC/AC time. Not PIC by way of 'sole manipulator,' a 'reg change,' or 'seat switching.' The few 91 operators I am familiar with do switch seats leg-by-leg, or day-by-day, BUT most of the time both pilots are considered captains, do make the final decision when in the left, and have very similar salaries.

Until that happens in 121 (never) the pilot whom autographs the release is the only one whom should log PIC time.

Cheers!