Do you have experience with an Aussie front locker? I have one waiting to go in and haven't seen anything really bad in reviews, just the front pushing a bit under power turns.
It's gotta beat a front open diff
Yes, I've run one in the front diff and rear diff on various rigs. Much better in the front. But makes driving in snow less safe, more difficult turning (at times) and decreases turning radius.
I would leave it open or ARB. Anything that decreases the driveability or reliability isn't worth spending money on (in my opinion).
In reality, I rarely use my front locker. Rear gets uses rather often off road. I'll flip the ARB front on to get over certain obstacles (typically only for 5-10ft sections of trail). Rear CVs are much stronger and will handle the locked diff without breaking.