It depends on a several of things.

1. About how deep are you windows.
   2) Do you like the trim around your window opening.
   3) What type of treatments are you considering.

1)The blinds can NOT be placed "inside" as there is no depth(no sill either)..
2)Trim is fine,though not spectacular
3)Wooden Blinds with a single panel curtain "treatment"

Thanks for your help!!!

Then I would make them a outside mount and cover up all the trim.