1. Think of it as a very fast patrol boat that can be uplifted as/where needed. The Soviets had 100's of OSAs that would have been very effective at coastal defence/attack.
2. Excellent at supporting amphibious forces.
3. Prevent (and destroy) USS Cole type attacks.
4. More effective than a Wessex V with twin fixed forward firing GPMGs - yes, Junglies did have such things.