It is ok BUT they should not pester for it.
It has been known for buyers to leave a neg saying here is the feedback you asked for.
Feedback is not mandatory and if you do not want to leave it then you do not have too.
I would be telling the seller you will not leave any feedback if they pester for it and if they continue they might not like what they asked for.
If any feedback is left it will be done to suit the transaction.
