Now that I have tasted the flex and LFR raids, I am usually disappointed when I don't have enough time to actually log on for a couple hours and join raids. My recently leveled DK is specced for DPS, so the queues can be upwards of 30 minutes. I don't have a high enough item level to join flex raids using oqueue yet, so I'm in the middle area of limited loot and long waits.
Every week I use a bonus roll for both Ordos and a Celestials boss, on each of my four level 90 characters. Including the default drop, that comes out to 16 chances to loot a high level item off those bosses. Two weeks in a row I have stuck out entirely. RNG is quite frustrating.