The discount offered is very nice, but my only question is if they can afford to sell their stuff at a 10% discount to you, why don't they do that for everyone? I understand that it is a token of appreciation for doing business there, but I've always taken the approach that all of our customers deserve the best price we can offer regardless of who they are or what brand of tub they own.
As a side note on filter cleaning, pick up a quart of filter cleaner degreaser (not acid based, acids will NOT clean oils out of your filter), pour the whole quart in a 5 gal. bucket and fill with water until your filter is submersed. Soak it in the solution for a few hours, but don't dump out the solution. Reseal it in your bucket, because you can reuse it for 6 months to a year.