Hi Chris,
Vienna instruments Pro - Very nice, feature rich, sample player for all vsl instruments... You could go with the vianna instruments player and come back for this later on but, its a lovely plugin.
Vienna ensemble - This one is superd, i dont know your hardware but its gonna love this piece of software. For example, my multicore mac had heavy cpu peaks in logic studio as the multicore deviding (is that decent english :s) isnt all that good. In VEP you build up different instances which wil lend on different cores which is way more efficient. Besides that is has some great features as resetting samples and such (check overview video). It does take some effort to learn all the routing and building up the template, but for me this one got as important as my daw :)
Vienna suite - Very nice low cpu plugins. Really needed? maybe not as there are a dozen good plugins around. BUT, it comes with awesome presets, specially designed for your libraries which gets you going really fast.
So lets say:
Vienna instruments Pro: € 123,- (limited offer now)
Vienna Ensemble 5 Pro: € 200,- (limited offer now)
Vienna Suite: € 404 (limited offer now)
Vienna SE vol I BUNDLE (which includes the extended library too): € 535,-
Vienna SE vol II BUNDLE (which includes the extended library too): € 565,-
Total: € 1827,- Some money left for your next investment!
Good luck!
Kind regards, Mark
edit: and you will need a vienna key of course which is € 24,-