I used to run full ArmPen runes on my AD carries since they scale into later game better. With the current afk farming meta down bottom, I understand why it is nice to get flat AD instead, so that you can farm minions better.

The thing is, I already can farm minions just about as well as if I had the bonus 15 AD. What makes me unsure of which runes to run, is that if I don't run flat AD and the other carry does, I lose all trades with them and can get bullied out of lane. If you are against a Graves or Corki and they have the +15-19 AD from runes, you can't even attempt to trade with them if you are Ashe. When I do try, I end up failing and having to hide under tower with whoever my healer is.

If you can give me tips on what to do, that would be helpful. Really the only option I see is to run flat AD, so I can at least attempt to trade with them instead of getting stomped on.

i dont play ad carrys but i think arp isnt that good if u build standard ie, pd, lw, bt, ga build but its better if u build an armor shred build brutalizer or younmuss, bc, bt

Graves or Corki will still pummel you early game as Ashe, even if you make the change to flad AD Ashe has nowhere near the burst that graves or corki have level 3-4. Ashe shines as a late game carry with her kit.

ArmPen IS better if you can last hit without the flat AD when it comes to trading with enemy champs.

There are lots of other factors that may be at play, however-- Did graves start Doran's and you start boots? You will not be winning trades 1v1. Did graves have a Sona or Janna buffing their AD or armor, while you had an agressive damage support like Lux or Blitz?

I believe those extra damage did help more on last hitting , but less on harassing. Check out the post below. The post below has very good discuss what to do on laning phase.

http://na.leagueoflegends.com/board/....php?t=2138020

Ad runes for better last hitting/farming. Arm Pen runes for better late game damage.

It is a pretty simple concept. If you want to last hit better go AD. If you are good last hitting go arm pen. So yes it is worth it if you are a good farmer without them. Boils down to playstyle preference. I personally am only an okay farmer so I go Flat AD. Otherwise I'd be doing armor pen.

as AD bot carry i go AD runes for better last hitting and more early game poke, with last whisper as my 4th or 5th item

I only use ArP runes for jungle, which I mix it with attack speed or damage depending on jungler, or on certain top solos with low ratios, such as renekton

It has not been good to get full AR Pen on the carry for a long time now, like 1.5 years.

Good early game means a better late-game scaling, with LW pretty much covering all your AR Pen needs. Ar Pen + AD combo runes gives the best early game while still giving a strong late-game transition.