We should note that this kind of data isn’t going to be useful for security purposes - the US Customs office has invested in a $15 Billion tracking system that (hopefully) leaves this one in the dust.
sounds good, but they are based on free data. If it works out for them, someone will jump it and offer it for free. Even though there is not much reason...
That's why Google would have failed completely if it required a monthly subscription (actually Google's a bad example since it was already a crowded market full of free search engines, but whatever).
Wouldn't put too much faith in that...