I am using both: Synchrosoft for Cubase and VSL, iLok for the PLAY-Version of the EWQL Orchestra Gold.
I never experienced any trouble with Synchrosoft, but just recently I upgraded my EWQL Orchestra Gold from the old "Kontakt" to the "PLAY" Version, therefore the iLok-Key came into my life (it wasn't needed before).
It's hard to tell what actually happened: most probably the authorization code was wrong...anyway: it took me more then 3 weeks to get this solved, although the support at "soundsonline.com" tried to be very helpful. Nobody trusts you, when you contact the support and write "I already tried everything, but the authorization code seems to be wrong. Dozens of mails and 3 weeks later they offered me a new license, I could download from iLok.com to my key.
I wasn't amused. And I keep asking myself, what a poor musician with little knowledge of computers would have done.
Maybe this was just a mistake of the software-producer, not one of the iLok-people... but I definetely don't need more of this!