So yeah, pretty mediocre, at best. The MC was involved in the first dungeon break (as was most of the world), and suddenly EVERYONE who was a player - even if they were dead lol - regressed, except the MC. Due to that, he gets a stupidly OP ability that basically gives him infinite stats, when you get 3 per level. So in like 10 minutes, he's a level 40 equivalent, and in days he's a level 338.
More importantly, he's also an asshole. By the way, everyone in the entire world is apparently also an asshole. He gets people trying to murder him in like 2 minutes, because they think they can therefore get all the stuff he got in his last life. However, he's an amoral almost villain-protagonist, who flat out thinks the weak should just die. It makes it hard to care about the story when literally everyone except his young-teen hero-worshipping sidekick is a terrible person.
Combine that with the fact the setting makes no sense and there's huge plot holes and this is a thorough drop. I can't tell if it's just a terrible adaptation, and the original source actually makes sense, or it's just terrible as well. For example, despite this being literally the first dungeon/skill/monster/break/portal EVERYTHING... somehow there's already an industry set up to support players. And one guy has 10 years experience managing players. At first I thought that meant he was also a regresser and his '10 years experience' was in the future, but that doesn't make sense either. One of the issues was that because EVERYONE regressed, the reliance on the player association was nullified... so why is he an important person now?
But ignoring that one guy, there's shops fully stocked with potions and portal gear, drugs that were created in the future using monster drops are already somehow able to be made less than 10 days into the world, when the highest dungeon is like level 20. Or how about shelters? Emergency shelters that can house entire cities built solely for dungeon breaks.... are already completed worldwide in the first week. No exaggeration there - they're literally avoiding a level 14 dungeon because no one can get strong enough to deal with it in 6 days. (ch14).
So yeah, the setting has more plot holes than solid ground, the MC is a dick and so is everyone else. Not a single non-annoying character. Terrible.