I have no problem with immersion at all. If anything I am a bit too much into it. I get attached to my boat and crew and don't want to lose either. I tend to play as if this was real and I take no stupid risks.
Hells the last weekend that I had to myself (no one around to ruin my immersion. "Hun can you take out the trash"

) I didn't even bother showering I ate only what we had on board, a smoked ham leg, bananas and oranges, made myself a U-boat special coctail (just like in the movie) and slept in my computer room

(drooling on my keyboard), turned up the volume, at TC 128 unpaused, waking up every time something happened i.e. Aircraft spotted!
ALAAAARM!!