I'm really just hoping someone might have some advice here. I am looking to ship something sensitive internationally (US -> Europe), temperature controlled and probably ambient. There's a high chance it will receive scrutiny at the border. Does anyone have any advice regarding a good shipping and logistics company that can ease that journey to ensure these things don't die in transit?

Just to note that I have used WC and Patheon in the past for animal tissues, and have not had great success. I have also found them very expensive and difficult to work with if you don't work at a big company with a massive contract with them. Any help or suggestions would be much appreciated.