USER vs PEER (IAX TRUNK)

It was my understanding that type=USER is no longer required, and type=PEER should work as an alternative.

Here is a problem I have have on the ONLY trunk.

OUTGOING (voice-out)

host=iax.domain.com
context=from-trunk
type=friend
username=99
fromuser=99
sendrpid=yes
qualify=yes
canreinvite=no
insecure=port,invite
secret=password

Now if I have the INCOMING (voice-in) set up like this;

type=peer
context=from-trunk

and I try an incoming call, I dont get the call. I dont even get the traffic. When I do a iax2 show peers, I have two connections, one for OUTGOING, and the other for INCOMING (which is unreachable)

However if I change to

type=user
context=from-trunk

The second connection (unreachable) is no longer there, and I receive the call.

So I am very very confused as to what is going on, and would love some insight.