Even some software like Milkshape that have not evolved from long years are still usefull for some people.
Silo has not evolved in solid modeling since v2, caus it has already all tools.
But these tools remain usefull for some people.

By re testing, i agree with Blender it's fast once you have defined main shortcuts for main tools :
-extrude
-loop select
-loop cut

Hexagon is great also for people wanting minimal and more visual interface for solid modeling !

After Re using it ; for solid modeling , not very very hight polygons, Silo is eay , fast , intuitive !

I would say if Hexagon is free go for it !
Blender is free, powerfull if you learn it , specially last version is lot more friendly
(You can try Silo , and perhaps spend some 100$ for that
great solid fast modeler)