A fully engaged locker will be a pain on dry pavement, but a LSD will not be the most helpful off-road. An automatic locker like a powertrax might click slightly while entering a turn, but from most users they say it is hardly noticeable. Clutches on a LSD will wear out and become less effective and need to be rebuilt over time. Both have their pros and cons. I want the no-slip due to its lack of maint., easy install (handtools in a driveway and not pulling the gears), and relatively cheap price compared to a selectable locker.
2003 Ranger supercab XLT 2wd 4.0 auto - sold
2004 F-150 supercab FX4 4wd 5.4 auto all black and silver leather interior...rockin' the fullsize