The best combination is all Military Armor, any eyewear (preferable night vision goggles), goth pants, any type of heavier winter wear-like clothes for a shirt and a gas mask. All of which at 600 quality. If you want to know cheaper alternatives, best ways to obtain said gear and an in-depth look at the world of armor, take a look at the guide.

The best type of armor in the game is the armor you got, but if you play pvp you may want the advantage of being able to take a few more bullets. The best methods to gaining that edge are leveling up clothing/armor, armor crafting for raising the max durability of armor, and of course getting the items neccessary for a max of 600. All percentages talked about in this guide will assume you have reached 600 quality armor as well as maxed clothing/armor. Any deviation from max everything will significantly change the values.

Durability is vital in armor. Since protection scales as a percentage of overal durability, it can and will drop fast. Half durability max quality military armor will perform woefully poor in comparison to max quality iron armor at full health. So a general tip is to bring enough repair materials to repair armor if caught in an extended fire fight.

Military Armor is the clear champion when you compare the stats. Military has 90% concussive and 95% puncture followed only by iron/bandit armor with 85% concussive and 80% puncture. A full jump of 15% in puncture from iron to military is MASSIVE. Puncture is resistance to bullets and with the objective in mind to outlast swarms of bullets this jump is HUGE. The biggest improvement to your overall ability to tank damage will come from getting 600 quality military equipment. (Sidenote)If you put Bandit Armor and iron armor side by side, the stats are the same right down to the durability and sale price, making it just reskinned iron armor

Surprisingly enough, this one is simple. Any eyewear you can get to 600 quality is just as viable as any other type of armor you can get for your eyes. The only small caveat to this is that night vision goggles do emerge on top only for their durability. Night vision goggles have 300 durability compared to every other type of eyewear hanging at 180. This means it will take the damage values longer to plummet than other types of eyewear, but is still nothing to brag about. At 300 durability it is still measly compared to military armor's 700 which loses a significant amount of protection even with minor dents in the durability

Take your pick, poncho or duster. Both have 50% puncture and 55% concussive at the same durability. I prefer ponchos since i can craft them and freezing allows me to get up wellness. All the alternatives had lesser stats than the craftable poncho and lootable poncho.

The best protection in this category is the sweatshirt, flannel, and hoodie. They have a durability of 200 and a puncture/concussive protection of 40%. This is in comparison to the fiber shirt which is 31% puncture/concussive and at an even more measely 140 durability.
This category has the lowest durability out of all of them and these are almost always the first to go in a firefight as a result. Even the best clothing at 200 durability is 1/3 of military armor. Always carry repair materials for these items.
As for obtaining these items, there is a catch. Clothing of different colors do not mix. Meaning if you find two sweatshirts of different colors and want to combine them for higher values, you simply can not do it. This makes it so you will more than likely only be able to wear the clothing you find without much material to change that. As long as the stats say they're above 31% of the fiber it is worth wearing.
Keep in mind any substitutions can affect your protection, but don't fret about it. Switching from a top tier shirt to max quality fiber will only drop your max protection from 106% to 104% assuming this is the only concession you make.

Changed 11/12/17: Thanks to OUYAAAAA for pointing this out. There is a big piece of clothing i missed out on. Goth pants are still the best piece of clothing at 50% punc./60% concus. but animal hide clothing can actually be made with nearly identical stats. Animal hide has half of the durability and 5% less concussive, but makes this piece an incredibly accessible alternative to goth. As for the obtaining goth pants, the best way to get it is to shoot biker zombies with a 4.59% of dropping.

Hands down, the largest difference you'll notice in your armor is whether or not you're wearing a bandit mask. It has 85% concussive and 80% puncture at 800 durability. Technically you can replace this with a bandana, but your protection would drop by 9% and even a grey quality mask would suit you better than one of these. Just harass the traders until they pity you enough to give you one.

Traders are great for night vision goggles and bandit masks as they will tend to carry them every 3rd time with maxed out secret stash. You'll quickly get these in spades if you visit them often enough (and they also tend to sell great weapons too!!). They are poor sources of military gear though as it comes very rarely and often in low quality. To get the actual armor, you need to raid military camps and missile silos. The benefits of this is the gear you find will be affected by scavenger and get it high enough and you pretty much wont find lower than 300 quality. The actual stats if you're interested is Ammunition boxes give a 7% chance of a military gear drop and military zombies a 20% chance. So even horde nights are a great opportunity to get military gear with these zombies coming to you.

As stated, durability is so vital to protection that you are essentially caught with your pants down if you dont keep it high enough and you can use that to your advantage. What many top players will do is run around with some type of explosive. A crossbow with explosive arrows or a rocker launcher. These will consistently break armor entirely upon hitting someone, but i have yet to see it kill anyone upon hitting them when they have maxed out armor. So this trick is best used when shooting from some type of cover at medium range or short ranged (if you can guarentee a couple of seconds of safety) to pull out a main weapon or reload a launcher for the killing blow as they have now become mortal. For most other scenarios, well placed headshots or an ak battle to wear down armor will tend to be the go to for most players as there tends to be less gear to carry and the chances of finding other players with top tier gear tends to be low.

The world of pvp multiplayer can be a nightmare without proper knowledge of the game. With no tutorials and hardly any guides the skill gap between the lowest and top players is massive. If this guide becomes popular enough or the demand is high enough i will make other guides such as an indepth look at what the values mean for armor, how to make an unraidable base, and lastly what ways there are to raid bases. I hope this guide helped you and see you next time.

P.S. A summary picture of what i put up can be found here with greatest - > least ordering. (some of the items of similar quality were put next to each other) http://gtm.steamproxy.vip/sharedfiles/filedetails/?id=1172998700.