I have many of those libraries going back to the old Kompakt EWG, which I run in Kontakt, not the EW Play, with SIPS 205.
I really think that the all of the EW stuff sounds great, but if you want to "CONTROL" (rather then use prerecorded one size fits all artics-and there is value in that-I've used them for years-but you have to write to the libraries limitations and capabilities with them) things like sus to trill (or any artic combo) transitions, independent (bynote) tuning, Vel xfades-cc xfades, etc, all of which you will eventually wish you could do, then to my knowledge you are going to have to look at the Players even before the libraries. The VSL developers Instruments Pro 2 and NI Kontakt developers with KSP scripting plus SIPS & WIPS have always been a step ahead of most others. LASS SAMPLE MOD, 8DIO, SPITFIRE,CINESAMPLES are all genius programs built using Kontakt. Play 4 is still a ongoing rumor, for about 3 years now. That said, Nick Phoenix-Thomas Bergeron are amongst the best at this stuff, libraries like SILK are beautiful instruments and I own 7 of their libraries, but you have to run there stuff in Play.
One more thing tho, if you choose VSL. They by far provide the most in terms of articulations, instruments and probably playability. If you want to write like the 80's polish guys for film then you need artics beyond Legatos, Trills &Stacs. They are also ther only company I know of that has a modular download, ie you can buy just a Solo Clarinet.
But make sure of how you want to work before starting to spend money with them or anyone. Are you going to layer? If so, with Ensms or Solo Ens combos. Will they phase?
With VSL, if you want to lean towards Solo Instruments, you may want to invest in independent but articulation rich Solo String,.WW & BRASSES rather then the Orchestral. The Solo samples from both sources are from the same pool so deciding you want to go to solos after buying the full Orch with Solos means you're buying a lot of stuff twice.
But all of the companies run Vid demos now. Watch the VSL,8dio,SPITFIRE,CINEBRASS, QL, PROJ SAM, SAMPLEMOD. (I own stuff from all of them) watch how the vids utilize controllers andd afterwords come on forums like this with questions about workflow because once you've bought you can't send it back. And think Cubase or Logic, the most liquid of sequencers for this work, something you'll start to see as you go the tough the forums. Good Luck, don't rush your choices as they all cost you $, avoid GAS (gear acquisition syndrome)!!