Well if you do decide to place him you may want to get the adoptor agree to give you "first right of refusal" if he ever has to find a new home.
Also you might want to find out if he has a good history with previous animals (i.e. so you had a dogs/cats/whatever before...what happened to them?) If he remains devoted to them until they are ancient and arthritic he will probably be a good caretaker for your BP, if he has a history of getting new animals and then not keeping them that says something too.