I just finished swapping in my 02 Forester 4EAT a VTD multi plate center diff from a 02 4EAT WRX donor.
The characteristics remind me of the 5spd AWD setup. The reason I say this is because of the wandering it has up front when you apply throttle. The VLSD center diff on the 5spds aren't the best in keeping the front and rear tight. The lockup is "enough" but not enough in my opinion. So in comparison without any hydraulic pressure utilizing the multi plate clutches of the VTD differential, it operates as an open differential.
The clutch plates are 2 less than your transfer clutch units (3 vs 5). I hope that the differential action does somewhat help. I will have to test how well it holds up in dirt/rock climbing situations where wheel slippage is minimized.
Now it's hard to tell the rear biased because I have a welded differential in the rear. It's also snowing in MN right now. The rear end does step out when I give it throttle, however the welded diff plays a big part in that. I would say it is feeding as much as it can since the rear does come out when I don't have the clutch plates engaged via my switch.