Where slug flow may exist in a piping system, is a snubber the proper element to use to dampen the impulse forces in the piping?

You would only use the snubber if it is an occasional occurrence,not if it is a continuous occurrence. If you want to lock it in place, use asway strut. If you want to dampen the impulse forces, then use a sway brace.

Hydraulic Snubber Assemblies for a LNG Processing Facility in Peru