Hi Dobbs1101,
If you order one of their Amazon mattresses and have the mattress fulfilled by Dreamfoam (not by Amazon) then you would receive the bonus they offer to the forum members here which is their pillow bonus. The 5% discount applies only to the mattresses on their own Brooklyn Bedding site not to their Amazon mattresses.
If you have the order fulfilled by Amazon it will be a little more and there is no pillow bonus (Amazon is not a member of the site) but you would have more options for delivery and you also have the benefit of the Amazon return policy (although this would have to be returned as a large item requiring truck freight once it is decompressed so returning it would involve some costs that are significantly higher than their return policy for regular items that can be returned through a courier service).
To get the 5% discount that goes with your membership in the forum here for their Brooklyn Bedding mattresses you need to call, email, or use their chat to get the discount information before your purchase. For the pillow bonus that goes with their Amazon mattresses there is no promo code but you would need to let them know on a phone call or email that you are a member here (and again this only applies if Dreamfoam fulfills your Amazon order).
Phoenix