I know this doesn't make it technically wrong, but I just want to say I've only ever lived in the US and have been around for 30 years now, and I've never heard someone say or seen someone write "we are unlike". I've only ever heard/seen "we are unalike".
It's very possible I just don't read enough books and there are plenty of examples of "we are unlike", but at least as far as every day speaking goes, I've only ever heard "we are unalike".
"Unlike" is still heavily used, however. "That's unlike him" or "You are unlike me", but never "we are unlike"...
We are unalike.
We are unlike you.
They are unalike.
They are unlike us.
That's unlike him to do.
He is unlike us.
He is unalike? <-- Does that actually work? If not then it may be that unalike is used when a plural form compares to itself.