If you go with an aussie then you should really consider a posi-lock kit so you can disconnect the passenger axle when you need to make sharp turns off road.
I've read a bit on pavementsucks.com about them because I was thinking of getting one and I decided not to, there are too many stories about people that get one and go off road, then hammer on it in a turn and cut the wheels straight then snap a u joint because the aussie wouldn't let the two axles free wheel for the turn.

 

Just an FYI You need a new carrier for the front on our trucks. The carrier breaks are 3.92 and down or 4.10 and up.

Price will depend on what you get and how much you want to pay.

 

You can get a thick cut ring gear instead of buying a new carrier.

 

But if he is going to put a lsd in the front he wont need a thick gear.

 

for what its worth this is your best option stated; the detroits a great way to go, and will behave similar to the Aussie. its the cheapest route to be locked front and rear and you will LOVE that.

also, regarding the lunchbox lockers (aussie, locrite etc) i have never seen one blow up; i've seen carriers split and axles break, but not the locker itself.
i've run one for years in my fullsize ford f150 that was a DD. the thing was great. i had no adverse tire wear (40000km put on it) and no unusual wear on anything; truck handled just fine, cept on ice; i would always be in 4x4. just have to be careful to keep tire pressures even, rotate tires, and litterally have to 'relearn' how to drive. in mine, i didn't even know it was there.............
if i ever build up anything again, i would NEVER run a selectable in the rear; if it fails to engage (cough, ARB) then ur hooped. those aussie lockers are strong; and for the rear, its a great option.

in regards to buddy that spit out a ujoint on his front with an aussie; that is just what happens when you have a locked D44 and bigger tires; not the lockers fault; an ARB or electric locker would net the same result; (broken joints)

sorry for the essay man; but in short, if you care about offroad performance, a drop in locker is the best mod you can make; plus you have more money left over for a selectable up front; so for an extra 250$ you will be locked FRONT AND REAR and everybody will be jealous.

regardless what you do, good luck

 

If you get a locker, that won't be an issue. Most LSD's won't either. Unless they are old and basically worn out.

You don't want an LSD, or Locker in the front. The Air Locker would work. Reason being, the front tires cover different distances when turning, and if they are locked, on pavement, the truck will not want to turn, it will just want to plow the tires, and keep going straight.
Less of an issue off pavement.