It is a rarity that I would use solely one instrument for a sound. There were times I had used a sole patch and I found the quality good. You have to know though that I am hyper critical of sound. If it sounds artificial in a way I don’t like, I will move onto something else, but that being said, I find most sample libraries to sound fake, especially programmed drums. Can’t stand programmed drums.
Anyway, I think kontakt is good. A loooooooot of people use it and there is a lot of additional libraries available for it. I think you want it but just need a nudge to pull the trigger. I don’t think you will be dissatisfied, I wasn’t and I would tell you if I was. Just what I wrote above.