1.) They say Muhammed was the last true phrophet, yet they also claim Jesus was the chosen one of God. When I saw this, I lol'd.
2.) Extremely hypocritical and contradictional manner of conducting faith and treating followers, especially women.
3.) Pedophilia. Enough said.
4.) An alarmingly amount of Muslims are radical. Radicals frequently murder Christians. You should be familiar with that, it tends to happen in your geographical location.
5.) I've had Muslims tell me they hate Islam.
Any order that oppresses women and treats them like garbage, with a zero regard for other beings is bad in my opinion, not to mention they contradict themselves numerously in the Qu'ran.