R-boats were pretty good minesweepers; the Allies let the Germans keep them after the war to expedite removing all the war mines from the North Sea.  And West Germany was selling new models to smaller nations well into the 50s.

The Schnellboots (S-boats) were exceptional patrol craft, and were probably the most effective vessels in the Kriegsmarine's surface fleet.


The T-boats were a mixed bag.  A lot of the older models had a number of problems, but that's to be expected from a navy that wiped out generations of institutional memory to comply with the terms of the Paris Peace Treaty.  The ones developed during the war did their job well - but then again, most navies' mid- to late-war small craft were effective.  Navies that didn't adapt to the realities of combat tended to not be navies real fast.

advex101: UNC_Samurai: Schnellboots

Schnellboots were actually E-Boats

E-boat was the Allied designation.  S-boot was the German colloquial abbreviation.