I don't know anything about Aussie locker's products, but I know my V-6 Lockrite works great.

The main difference between the 4 cylinder and V-6 Lockrites is the lack of parts in the V-6 version. The Lockrite version uses the factory spider gears and actually works quite well. No breakage is over 5 years of use for me, with a rig that is almost never under 5000lbs. I suspect, from my experience and hearing of the 4 cylinder lunchbox lockers that this design, with the less aftermarket parts and utilizing the factory pinion and side gears is a stronger set up.

I'd be interested to see how Aussie builds the V-6 version. But unless it's MUCH cheaper than the V-6 Lockrite, if it were up to me, I'd go with the proven product instead of being the guinie pig.