Alright, first some issues at a glance:
1) Mastery section needs to be updates from Season 2, the information there is outdated.
2) Item section as well, you recommend Iceborn in the core but in the items section you say that Triforce is core, as well as some other embarrassing out of date bits (Madred's).
3) You do not have the Summoner spell Barrier listed anywhere in the guide, it's a great skill. In my opinion, Ignite, Barrier and maybe Teleport are the only summoners that even have a chance on Ezreal (Not counting mandatory Flash). Your section here is also out of date, listing spells that do not exist anymore. Barrier is awesome and my personal pick though, you should try it (Much better than heal considering a lot of popular ADC have a 50% heal debuff such as tristana and MF, and to top that off you have enemies running ignite). Nothing is more satisfying than ruining a cait, karthus, ezreal or ashe ult by using this spell, also great for dueling and ignite counter.

Anyway, good guide, very detailed. I mostly read guides for opinions, but it was kind of hard with yours since it's sort of out of date. I seriously recommend updating it. I find myself to be a pretty proficient Ezreal player (I haven't played any ranked, but it's out of choice thus far, I don't really want to get into it at this time) and I'm always questioning my build.

What could work better? What is best for more situations? etc. Which is why I check guides for the information/opinions. Currently having an internal debate over:
23/0/7 = Flash+Teleport, Distortion boots = ~185s CD on both TP and Flash, on Ez this gives extreme map control but hurts your dueling and survivability.
21/9/0 = Barrier+Flash, Furor Boots = Great dueling/survivability and kiting, less map control.
22/1/7 = Barrier+Flash, Furor boots = Better overall game with lower summoner spell CDs and early mana regen, but you lose the 5 armor and 30-138 HP which hurts your duels.

Very tough decision for me, though I am leaning towards the second or third, the first is awesome late game but getting to late game is harder, plus you lose the kiting from Furor boots. I also wonder if Muramana is viable? It is very overlooked, but above half mana you will be hitting for +75-150 physical damage per autoattack while the passive is on (Phys damage benefits from armor penetration, lifesteal, etc) and you are also getting (1045+500+1000=2545/100=25.45*2=50.9+20=70.9) almost 71 AD with it. It gives 1000 mana, 71AD, extra physical damage on hit, and 7MP5, for ONLY 2100g which makes this a pretty awesome item. The hard part is getting it though, since you need to buy a ToG early to stack it which can really harm your lane, once it is stacked though, you pay 1400g for all the prior listed benefits.

Also, while I'm on build ideas, you really need to throw Statikk Shiv or Phantom Dancer into this build, you have little Attackspeed and not enough crit.

+1

Well no.. But looking at some "pros" play, I get annoyed with some of the decisions they make and feel I could definitely do better xD

Wow, Challenger already?

Great guide, but I have to question Ezreal being "A difficult if not the most difficult champ to master" ^^ I actually think he's very easy to master.. Not a whole lot to him at all apart from skill shotting ^^

First time when I read ur guide some months ago I would have completely disagree with what u said about Caitlyn , that she's the weakest adc out of all . Now, however , I must say that u're right , Ezreal and a lot of adc simply beat her because she has no way to harass back , for example: If I use E+AA+W+Q as Ezreal , all that she could do is to use her Q which can be avoided or Auto-attack or simply use E and run which will result in a lot of damage she had taken and minimal damage u took. Also her mid-game sucks as I saw in a Caitlyn guide and I understand why so if u get a few kills on her, she'll pose no threat to ur team.

Very good guide ,I like it the most out of all Ezreal guides.

P.S: That Iceborn Gauntlet is great , I kited a lot of people to death ^.^

Actually, I find Caitlyn to be a challenge to me in lane. She also outscales Ezreal lategame. And I feel that Caitlyn has larger autoattack so she can hide behind her minions and poke you without recieving a Mystic Shot to the face.
And btw not sure if you included it into your build but you might want to try out rushing Bloodthirster and Statikk Shiv. Just try it out even though it may seem weird at first as I feel that these 2 items help Ezreal to shine midgame.
But I like your build and explanation :)
And a VOD you could add was Rekkles' Ezreal, his Ezreal is a beast. He was from FnaticRC.

sorry xD.
It was an impulsive string of text there haha =P

Being a Tristana AD Carry I take some offense to this: pushing power equal to a girl.. :P

I can push pretty hard with Tristana

1. His passive that gives you 50% attackspeed is extremely useful.
Throw one good Trueshot Barrage and your damage output is increased by 50%.
Absolutely not pretty useless, but in fact a very strong AD steroid ;).

2. A second bloodthirster won't work with a good team against you.
More damage does not necessarily mean better.
If you get focussed you are dead in seconds.
On the other hand, with a Guardian Angel you might be able to sustain the damage long enough to kill a couple of enemies yourself.
Either that, or you will revive because of te passive GA is having.
You get a second chance to do damage, which is a lot more beneficial than more damage.

I hope you think it over =P.
Cheers,
Ex Vi.

Love ur guide, an adc with actually sustain works mirracles. I prefer a second bloodthirster though over Guardian angel ur still the massive dmg output and not the tank. And its passive is in most cases pretty useless anyway.

The build wasn't 100% ?
Can you try to explain that a little more ?, cause your reply is about the same as saying to a very ugly person : "yeah, you are really really ugly, but I don't know why. Bye!".

Good guide but the build wasent 100% :) wish u the best of luck man!