I would have both personal and airframe chute for testing. Reason - while spin testing a local design here in South Africa the plane got into an un-recoverable spin. The airframe chute was deployed but failed to be come out of the aircraft. The two test pilots then had to exit the aircraft and were saved by their personal chutes. Had they relied on the airframe chute they would not have survived. Do you know your airframe chute will work properly? Theirs did not.
Neil