The reason I've made the Thomsen's Dials Mod is exactly the crush depths.
I was sick of being to pass 260 meters (for a small margin) and see that needle get stucked in 258 meters (look close and you'll see that its not even 260).
Im my mod the needle goes up to 315 meters, near the zero mark (complete turn), just like it was in real uboats. I will not spoil the fun telling how far can you go, but I'd say I've gone beyond 260 meters in some rare occasions with the types IX without breaking a sweat. Well, not actually withou breaking a sweat, coz those cranks and the tension is pretty high.
And dude, throw away that No instant deathscreen 1.1. Lots of bugs. There's a version 1.2 in my FF page.