high quality of musicians and the best sound I ever heard about the jazz backing tracks.

I play vibraphone as a hobby. I have a half dozen Joy Spring backing tracks on file. Of varying quality, but all useful at some stage in learning the tune. Along with these I have a similar number of Joy Spring instrumental solo tracks I play along with to pick up timing and style hints.
Of the backing tracks the one from Jazzbacks comes out on top for two reasonss. First is the shear musical quality, and second the clincher. It has the full original intro.