Smarthawke,
I've used one of the firms you quote, and yes, they did a fantastic job, but at a hell of a price (BTW, I can think of a few more who would argue with your "two reputable companies" statement!). But as you will see from my post, this firm is also supposed to do a "fantastic" job : and as they are evidently JAR-compliant, or certified, or whatever the phrase is, I can't see certification being a problem, Eric.
You're quite right about the ferry costs, of course, but then that's my problem ...
FF