I have never heard of Faultless ... we can't get spray starch here any more.
I agree Best Press does not give as much stability as a full on starch.
Some of the LQS' now carry "Flatter" instead of Best Press.
I have tried it, but IMHO it has nothing in it ... I might as well just use a water spritzer.
Your starch should have things nailed down pretty good for you.
.... plus will have any fraying stopped flat!!
It will make for a nice clean back.