This is Madam Enigma first of all... On a trial account atm till I have the money to renew my main account. Later I'll likely get architect edition for the 2nd account.
Anyway, my 2 influence on FA. It's nice to have in PvP, but otherwise I personally rarely turn it on. Some mobs I will, such as with rikti drones, but really that's a rare exception. Madam Enigma is a claw/sr scrapper though so your millage may very. It's interesting to note that I've only 'recently' started slotting IO sets. Even with using SO's I was finding one acc in each attack was generally enough to hit 95% hit rate on most foes. Since I tend to run on the 4rd difficulty, that is even more the case.
Why not Ruthless/whatever the hero side is called (I forget)? Because I find that twice the enemies at +1 level gives more xp/inf then +2 mobs normal spawn size. Yes, I know. It's blasphemy. But consider the facts. You can drop two or three times as many +1 mobs usually as you could in the same length of time for +2 mobs. This is in part because not only is it easier to hit, but you do more damage vs the +1. Remember, all your powers are less effective on +2 mobs. That means less accuracy, less damage, less mez effect... Overall you get 1.5 times as much xp on the 4th difficulty as you do on the 5th one.
And teaming of course exasperates the difference. A full 8 man team on the highest difficulty is fighting +4 mobs, and double the normal amount.
A full team on the 4th difficulty might be facing +3 mobs, and quadrupedal the normal amount. Which team will get more xp/hour?
