hard disk LaCie USB 3 to MacBook Pro (2011) USB 2

Dear Community,

a question about an extern hard disk !

I use an MacBook Pro February 2011 with USB 2.

I want to by an hard disk La Cie, 1TB, USB 3. In the description they say: you can also use USB 2 with this hard disk.

Ok, so there should be no problem.

But i've found informations that there can be trouble with the current, because the hard disk gets not enough power from the MacBook Pro -USB 2 - to the disk USB 3.

Is this true?

Does anybody have experience with this hardeware combination?

Trouble or does it work ?

Hope to hear from you.

Nice day,ciao

1Ffm