Yesterday, signed up for my 3rd account for myself and 3rd account for my spouse. Everything went smoothly on my signup. Hers remained in the "identity verification" process for about 24 hours (and therefore wasn't able to send or receive money), but seems to be up and running now.

Will now start doing each month:
A>B, B>A
A2>B2, B2>A2
A3>B3, B3>A3

If it continues to go well, I may just have to add A4/B4 in a few months.