Climbing things like Napolean hill (steep hill slippery when wet and almost drivable all open in perfect conditions) with a front locker is a little different to only a rear locker or all locked I will explain the differences.
All locked (doesn't matter the type of locker) if you end up spinning all the wheels you can pivot around the one with the most grip loosing the front end or the back but you react quick counter steer or get out of the gas and find more grip.
A front locker (doesn't matter the type of locker) as far as cornering with power on the wheels will be traveling at the same speed this will make the terrain have to allow one tyre spin to corner with a front locker your turning circle is wider than an LSD but you know the wheel with grip is the wheel getting power.
with a rear locker you will be pushed straight or if the front has more grip can pivot based on gravity and slope angle (or around the big rock that jumped in front of one front wheel), if the front has some grip you will be able to point the vehicle where you want but with some oversteer effects with only a rear locker you will be pushed straight or if the front has more grip can pivot based on gravity and slope angle (or around the big rock that jumped in front of one front wheel).
Climbing a loose slippery surface with a front locker only (doesn't matter type) should be safer as it will keep the nose pointing in the right direction if there is grip.
What would I choose, with the selectables and locked offroaders i have driven I have front LSD (looser than a girl i knew

) and rear Lokka and learned how to drive it and react to it (didn't learn enough about the girl tho

) the thing is to learn the vehicle and be confident in your decision making, I have seen someone in a ARB equiped offroader get it all wrong and fall off a hill where the next vehicle (with only an LSD rear and body lift) drove with confidence and didn't panic or have everything to turn on then right foot expecting it to go there when it started going wrong (I think the family panic'd and this made the driver panic).
Drive within your limits and if you are unsure have the family jump into other 4wd's (or walk the section) and have someone jump into the seat byside you or talk you through with a radio, there is no shame in admiting you would like some help learning what the 4wd is capable of (where its corners are) and how to react, it is better for everyone to get through and have a great day than spend 5 hours recovering people gear and the 4wd (no one was badly hurt) but to get out the 4wd needed a bit of effort.

bit of a Grave dig but the poor Landrover only just fell off the hill now

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