Nico, and what about a good old hardware sampler?
The Roland S-760 for example, is considered the best sounding S series sampler and today it can retail for 150 Euros, with full memory (32 MB) and the digital I/O option which included mouse and Monitor option (you can hook to it also a TV if I am not wrong).
Hans Zimmer used to have 18 (!) S-760 for composing his music and it's plenty of really good sounding libraries on CD-ROM. And, by the way, you can load and save from SCSI devices like ZIP/JAZ and CD-ROMs which sell on ebay at ridiculous prices too.
Or an AKAI S3000XL? It retails at 150-250 Euro fully expanded with 32 MB digital I/O SCSI 8 outputs outputs (just not for the Effect option board EB-16 which is the same for the MPC-2000XL and that is still expensive today, new or second hand)
And a Kurzweil K2000R with 64 MB? Kurzweil was famous for their great sounding libraries, and it reads AKAI and Roland CD-ROMs, although it reads programs and samples with loop points but envelopes settings and other synth parameters are mostly interpreted.
And by the way, if you want to read correctly AKAI libraries the best way to do it is... with an AKAI sampler...!
I tried once an A/B test of an AKAI library on a S3000XL vs Kontakt and there was a BIG difference, especially if the library is carefully programmed for that instrument (envelopes, LFOs, velocity crossfades etc.)
Size does matter? Today's libraries are expressed in Gigabyte, with 24 bits as standard and a great waste of space caused by very long samples with no loop points (who cares today of looping a sample with gigabytes of RAM?) Untill year 2000 sampling was an art...!
I feel boring here, but I have heard a demo composed on one of those huge VST libraries like the Vienna or something and it sounded like a big MIDIfile...
So the skill is to know how to play them masking as much as you can and understanding where the samples feel natural and less obvious. And in the past I have heard people doing miracles on the AKAI S1000 with 8 MB of RAM...!