Came along this video on youtube:

 

It is a 50 min video where different cars drive over rollers, this time it is not a commercial but just normal people in Lithuania. It surprises me that most Subarus are not able to dive off the rollers with two side wheels on the ground. This most likely because most EU models have an open diff at the back. Actually most AWD cars have open rear diffs. However, at 4.25 an old audi quatro (Torsen awd system) also shows slip but then suddenly jumps over. I assume the driver uses the handbrake to send more power to the front.

 

Question:

With an open rear and front diff does using the handbrake to lock the rear and thus sending more power to the front help. And can it damage the brake system or center diff?

Using the handbrake transfers power to the other side, not just the front.  Subarus can transfer power to the front without doing this.  This trick works on 2WD vehicles too, and it's not particularly bad for anything.

 

I cringed watching the video every time people were revving while the wheels on one side were spinning.  The spider gears in the differential don't have real bearings and are not designed to take prolonged and large differences in wheel speed.  Luckily in this case there isn't much load on things, but still...

Subaru has three different all wheel drive systems. Some are more capable than others at overcoming a loss of traction on 2 or more wheels. This video shows that better. Hopefully this link will work!

http://www.liveleak.com/view?i=e05_1384810870#1v7oheuKRBoM9exD.01

Why I'm going to install a LSD in the front but I can deal with a stock LSD in the rear, aftermarket is a little too pricy and too much upkeep for me (clutch discs and LSD fluid)