That looks great, Lobo!  Yeah, the Instant Mesh app is good, but I'm not a huge fan of it for lower poly results.  It can provide a useable geometry for static models or some objects that aren't too complex with large flat surface areas.  I haven't found it very good for more organic or complex surfaces because it tends to produce strange edge loop terminations and ngons at lower resolutions.  It takes some work to get a good result from it at lower resolutions.  In some cases, I can just retopologize better geometry on a surface with 3dCoat in less time.

You are correct in that the Zremesher was created by the same person who developed the Exoside technology.  I've been using the Exoside or Zremesher solutions for a couple of years now and they really do a great job in most cases.  There are some objects that I made via boolean or high poly sculpting that I wanted to retopologize for distribution.  I tried to do it by hand but it was extremely difficult and time-consuming because of the various interlocking parts and curvature on each object.  The only thing that was capable of doing the job reasonably well was Zremesher/Exoside.  Well worth the money in my opinion if you do a lot of retopology.

______________________________________

My Store
My Free Models
My Video Tutorials
My CG Animations
Instagram: @luxxeon3d
Facebook: https://www.facebook.com/luxxeon