Marius

I personally use the Gold ProXP library myself, so I can tell you for sure that it's good, but no, it will NOT run on an Intel Mac unless you also have Kontakt, that is true and an unfortunate side-effect of Native Instruments discontinuing development on their Kompakt Player software.

I'm not sure why you'd be asking me about Gold though if you aren't even sure about running Silver. You can get Silver, in its PLAY edition (so without having to worry about Kontakt) for about half the price of what you linked to (the Gold ProXP bundle) — and let's not forget that you still have to tack on the $300 crossgrade price (Kompakt Player -> Kontakt) to that if you want to use the Kontakt version of Gold ProXP.

I'm also not sure why you're consistently ignoring my suggestion of GPO, which sounds like it's definitely your best bet, but it's your money, not mine. Another thing to keep in mind is what sequencer you're using. If you don't have one, you won't be using any of these sample libraries right off the bat, so that's something to consider too. What do you write your music in? If it's Finale, then as of 2009 you'll be able to use ANY VST sample library plugin (so all of the above) and I know that EWQL will work as early as Finale 2007. If you're using Logic then you're also good to go, since it has full support for VST plugins and runs all of the above like a charm.