With RAF, when the new/friend account pays for the first month.
The referring account gets one month free.

And when the new/friend account pays for the second month.
The referring account gets one Zhevra mount (for a single character) free.
That is an extra achievement, if you are collecting those with one of your toons.

With RAF, and four linked toons being boosted by a geared 80 tank type.
You can do 1-60, in 8-9 hours of played time, if you are half geared and are efficient.
I'm never that fast, but quite a few people have done it at that speed.
I can easily do 1-60, in a weekend, with RAF.
Even without a booster, if you were to RAF 5x new toons, it will be fast.

With the toons you boost or level, granted levels from the toons boosted, etc.
You could RAF toons on both factions or on two servers, and have near full accounts on each.
Three months of RAF time is quite a bit.

You also get to grant levels, based on levels granted to you, ie they cascade.
For maximum effect, you want to boost two toons, for each link in the RAF chain.