You just wind up getting into a problem when the barrel contour doesn't quite match up with the muzzle device contour or required setbacks. With the $150 that some of the manufacturers like charging along with the fact that it's generally accepted a thread-on suppressor by design provides a more consistent mounting point imparting that consistency to long range accuracy rigs if you play that game. I used to fight with my Surefire suppressors and their muzzle devices frequently.
With newer manufacturing technologies, more affordable titanium options, and serviceable internals, weight and length tend to not be factors limiting your selection.