tru trac or locker

When I ordered my S60 from Strange, they suggested the TruTrac over the locker for street use and I've got a bit more in my combo. 517" big block dyno'd 638hp 671tq without the spray. GM 4l80 with a brake and 3.73's in the 60 with 28-14.5/15 Quick Time Pro's out back.