Durability sounds good then!
Concerning spraying poly i found several tutorials stating the following:
If you want to apply several coats and you want them to bond chemically and not mechanically, the timespan between coats has to be short (10-15 minutes for the Spraymax 2K for example). Most of them spray several coats in short succession and then they wait, sand and then apply several coats again, etc.
Might be possible with wipe-on as well?