Something I have noticed when you filter loot options. Since crafting mats are white you have to pick up all common in order to also pick up crafting mats. Perhaps we can have a toggle specifically for mats?
After about lvl 25, the game gets to laggy, even with max armor and max minigun, the last 2 lvls almost to laggy to play. I lost all my lives exept the last one on the second to last lvl due to the lag. Blood was off, graphics on low, and a pretty goood pc. I could not even kill them fast enough on the last lvl to avoid serious lag.
In addition, I lost the will to play after lvl 25, as I had more then enough for the upgrades. I was interesed in seeing the end, but with nothing else to work towards it felt like a chore instead of a game. 250 hp is not enough at the higher lvls either, that is 1-2 hits to kill me with those zombies. Either add something to buy more hp outside of armor or talent/acheivement system to reduce damage taken and other perks. 3/5 because or the lag nd other things mentioned.