Engine is Best Service's version of "Kontakt" basically, howbeit not really in Kontakt's league, but
still not a slouch either. Most of the Best Service products run inside of "Engine". It's FREE, and there
is a huge FREE Library that gives you a few patches from all the Libraries Best Service sells! The interface
is OLD ( and it looks it!) but still works.
The BIG HITTERS are the Tarilonte Libraries, which are top notch...and the price reflects that!