Last Beta of Helix which still sounds good... Very low CPU for the quality of sound output, and only 491 kb DLL!.sure the first commercial version was even bolder but was not as thrifty as this beta (I checked/tested)... This is a keeper for sure... Comes with a few extra banks...
https://archive.org/details/helix-2008-4_202606
https://archive.org/details/helix-2008-4_202606