I suppose it depends on what you have and what you want to end up with.

You have A + B.
You could RAF from B to C.
And boost B + C, with A several times.
And then do character transfers.

You can just group A + B + C, and level as if RAF never existed.

If you're only planning on doing one team of three, this isn't that painful.

But if you'd like 3x Class A, 3x Class B, 3x Class C and 3x Class D etc.
The RAF route will be the one to go.
Because you can level up AA then BB then CC then DD.
Then you can grant two toons on B to 60th.
And transfer them to Account A.
And have something like AAA, BBB, CC, DD.
You could also then boost another C and D, on the two RAF accounts.
And transfer them both to A.
That would be four toon transfers, which isn't free.
But you'd have four sets of three characters.
And it would have been a small fraction of the time to get there without RAF.

In the end, its a preference call.