Ugh...another one of these kind of threads. If you are in Addicting Games you would pick addicting games, and if you are in Armor games you would pick Armor games!
This thread is already at the top, so I won't be hurting anything by saying this: these threads are pointless and clutter up the forum. Some people won't agree with me, but I'm sure whichever mod locks this thread will. There have already been a whole ton of threads like this. go look for them. If they aren't locked, then go post there. Unless they are dead, then leave them alone. If they are locked, then don't make a new one, because then some mod will have to lock it.
I used to be a big fan of addictinggames, but I pretty much never even go there anymore. The average quality of games is much higher on AG, and the setup is also better.
The setup at Armorgames is geared towards determining which games are better and encourages players to rate them. The ranking system shows that by awarding points to thoughtout reviews and ratings instead of the people with the best gaming skills. The interface here is also more user friendly to casual players, addictinggames is a little more complex. Armor games is the best I've seen, although, that could be because I've gotten used to it.