LaCie does not manufacture disk drives. They use other vendor's drives and put them in their own enclosures. The actual disk drive inside of the LaCie enclosure is manufactured by hp, Pioneer, Sony, Lite-On, or some other disk drive manufacturer.
My recommendation would be to use high-quality media, and stay away from bulk, no-brand-name media. I typically go for Imation or Verbatim media, falling back to the slightly sub-par Memorex media when better media isn't available.
Why not buy a 5-pack of some media first, test it, then go out and buy bulk if it works? Just because one particular brand of media works on one person's drive does not mean you'll have the exact same results.