Serious [Debate] Is it unethical to eat meat?

I do think treating any living being poorly is unethical.
I love my share of meat, but I try to stay informed where it comes from and if the animals are treated good.
But "good" is also debatable. My definition is each animal having a good amount of room to move, regularly cleaned barns (having an automated scraper that cleans the floor is enough for me), good food and humane killing conditions.
By humane i mean stunning them and the killing them fast and without or VERY short pain.

Everyone has his own definition, but if these conditions are met it's alright by me.