For all the people complaining "This looks Pay to Win!", I'll give you a story.
A couple of months ago my friend who was Chinese wanted us to play a game that was popular in China called Crossfire since his friend recommended it to him. Me, him, and about six other friends downloaded the game. Since we weren't huge fans of competitive multiplayer, we made a private lobby and played for a good amount of hours in our own match. We had tons of fun in there because everyone had pretty much jackshit and we were all on equal terms, since we didn't spend a dime on the game.
Then, we went out into the "real" game.
The first match we played was just a standard TDM of 6v6 (at this points 3 of my friends got off). Thirty seconds in, we finally encountered some enemies. I had the classical moments of rage where I screamed to the heavens saying, "How did she kill me? I thought I had the drop on her!" Obviously I did something wrong, so I tried again and again afterwards. After we got destroyed (42-100 about) I looked up the weapon most of the players killed me with, called something like Ak-47 Crystal Rage. There were also some players with AK-47 Green Demon, or Ak-47 Golden Dragon. I had a regular AK 47. I looked up the guns online and compared stats.
All the "different" AK 47's had two shot kills, high firerate, high accuracy, and low recoil compared to my regular AK 47 with 5-6 shot kills, medium firerate, medium accuracy, and high recoil. I looked up how to get these "special" AK-47's and realized to my amazement I could only get them through real money (approximately 10 dollars).
Obviously being ticked off, I suggested that we should play another game mode. We played a game mode of Mutation, which was like zombies but the zombies were huge hulking monsters. When all of my friends died, it was down to 4 survivors and 8 of us. They all had character models of "BigTitsnAssMcGee" and a bright green minigun. The minigun killed us within 5 seconds. Not only that, but if we got close the knockback of the bullets would literally send us flying away! After the match I looked up what it takes to get a minigun. Take a wild guess at what I found.
Still pissed off, we played a match of Predator, which was like we were super fast and invisible, while enemies had to stay alive. We got supplied with our default melee weapons, which were standard knives. They were around 3 hit kills unless you did a wind up backstab which made it 2 hit kills. When I died, I saw my teammate have this weird "jagged" curved knife (it kinda looked like a narwhal horn TBH) and it was 1 hit killing people all over the place. After the match I asked him how he got that. He said with money. I asked him if I could get it without money and he said quite casually, "Nope."
Pretty much all of the F2P FPS's I have played have had a model like this. Crossfire is one of the worst offenders, since it basically guilts me into believing, "I HAVE to pay money to be good".
Halo Online does not look like this. It looks pretty fair balance wise. If I had to describe what gameplay is like right now from my impressions, I would say "MOBAish" since certain weapons and weapon alterations are better than others in specific situations. Gun rentals are in pretty much every F2P FPS, as how else would they make money a lot? They could just do cool armors, but that would get them barely any money honestly.
One of the betterish F2P FPS's out there is Planetside 2. While not a Pay to Win, I would call it "Pay to Save". To my understanding, you can buy all the guns and stuff in there with in game credits, but buying it with money simply speeds it up. You have both options, but paying with money just simply gets you there faster.
TL;DR, if you have never played a P2W FPS and you call this a P2W FPS, check out a game like Crossfire and then you'll see the true understanding of pay to win. This, in my opinion, from my experience in pay to win fps's, does not look like a pay to win fps.