I am a relative tyro when it comes to on water matters, but I do know what I like and the Warlord Games "Cruel Seas" has always has quite a strong appeal. I finally pulled out the S-Boats that came taped to the cover of Miniature wargamer in 2019 out and painted them up over the weekend. They are really very pretty models and paint quite easily with some blocking in, washes and some very light dry-brushing to sharpen up the hard edges.
The model above is one of the S-100 class with the armoured bridge that appeared from
from 1943. Armament was officially 1 × 20 mm in the bow, 2 × 20 mm gun amidships and 37 mm gun aft. Mine seems to have gotten a sneaky Flakvierling in place of the aft 37mm...This is one of the S-38 Class. I am of the impression that armament was quite various and
included such treats as 40 mm Bofors or 20 mm Flak aft, MG34 Zwillingsockel (twin-mount) midships. I think mine looks like it might have a 20mm or 37mm aft. Quite tempted to leave all the weapons free in their mounting points so they cam be swapped around. Warlord to a nice range of additional weapons and crewmen that might serve to dress the boats up quite nicely.And here they are together. As to the apparent size difference, the camera and perspective are telling you lies. They are both the same length.
I have a pair of Vospers that will hit the construction and paint desk soon!