its pretty cut and dry, if you are bringing a hard coral or a coral attached to live rock across the border, you will need a cites permit. Additionally if you are importing a livestock order of any substantial size you will probably have to pay a US fish and wildlife fee. If it is worth it for you, great, all the power to you and I hope it goes smoothly for you and the livestock. some people get away with things thats they shouldnt because some customs agents are not very knowledgable, others such as most of the ones at airports will be very dilligent in regards to their job. I have gone to ridiculious expense to get ahold of certain livestock, so I know what you mean when you say its worth it. Its all relative!
(whatever you do, dont fall in love with any deep zone livestock, unless you win the lotto)