1 second behind the incredible 4 year old record by Desch. The fact that the record has stayed the same for so long says how impressive it really was, especially for its time.
I think the RNG needed to get a sub 5:30 run on 100% is very underrated. While i havent grinded for this as much as i did for sub 1 life raft, i have still done dozens of attempts trying to get an RNG like this over the past couple of years. I have gotten all 3 heavy items in engine room many times now, but the run has always failed to something missing in the upper decks. Even in this run, there were several items that spawned in the "wrong areas" (especially the sub batteries and welding kit).
A sub 5 is definitely doable, especially if you get all items in the correct area. Thats definitely my next goal, and i believe its the final minute barrier for 100% speedruns in Monstrum, unless some crazy submarine time skip of some sort gets invented...