It mostly depends on my secondary. Soul (which I believe is the End Discount?) makes it laughably easy for me to run my Damage Aura at low levels (Something I usually never do because of the end useage)
And Form of the Body's -Res debuff on Eye of the Storm is always nifty.
I searched for Perfection once. You know what it got me?
Yup. Darn near eaten! 
Clicking on the linked image above will take you off the City of Heroes site. However, the guides will be linked back here.
Roger that Burt, and congratulations. Be advised, however, that there are two more, repeat, two more motherhumpers.
American Dawg, Starblaze, Neanderthal Joe, Shining Dawn, Tokamak Dragon, Stinger Incarnate, Burning Tyger, Dover Tornado, Big Roach, Dark Paladin, Archmage Wylde, Kings Row Hornet, Prancing Deer
Avogadro, Science Lord
Edgar Nightcraft, Doc Cicada, Chupa Macabre, Dr Forchtenstein, Blood Shrew
I didn't do beta and I didn't read wiki closely enough so I discovered the buffs that perfection gives out yesterday and enjoyed them immensely. I started out with Mind at level 12 and the recharge boost was noticeable but I am /sr so I kept running out of end so I switched to Soul and even though the fights lasted longer I was able to keep going without eating many blues. At later levels you get to choose which finisher to use and either get more buffs or put out debuffs. I'd be interested to see what other people do in the higher levels, if you are lazy like me and just go for the buff you want or like to switch it up for different foes.