These drawings from DIE DEUTSCHEN KRIEGSSCHIFFE 1815-1945, vol. 2, depict the general appearance of a Raumboot in the R17-24 group and a Schnellboot in the S18-25 group.

A simple comparison between the photos of the model and these drawings demonstrates that the modeler based his/her model on the S-boot design.  This is evident in the torpedo scallops, full width breakwater with hatch, length of the rub strake and related doubling amidships, shape of the bridge, number and spacing of the airports,  etc.  The model does not remotely display the features of the R-boot.
Al Ross