Brekinapez, a few Tauchpanzer were successfully used for fording the river Bug on the eastern front.
Sorry, my bad. What I meant to say is that anything the Germans got finished to the point of sending a copy out the factory doors and around the parking lot for a spin at least, I would probably buy a kit of at some time or another as opposed to paper projects or unfinished and inoperable prototypes. So a Maus yes but a Ratte likely not (especially since I prefer 1/35!).