I uninstalled ATK a few days ago, and immediately I felt like it was a waste because it felt like the phone actually got a bit faster. This morning, I installed it again to find tons of apps open in the background that were the reason my phone had slowed down to a crawl shortly after uninstalling ATK.
I'm not gonna give suggestions, but ATK is back on my phone, and I'm less frustrated with it. I have a problem with hitting "back" to get out of programs, so ATK takes care of it for me every so often.
Spare Parts, or whatever that program was called, did absolutely nothing for me, which is why it was gone less than 24 hours after it was installed. The CPU monitoring is useless (what the hell is that, a live bar? Who cares how long Messages has been open and used, my phone tells me overall what keeps it awake), the screen transition thingy was nice for the first few minutes, then it was blatant (in a weird way) and I felt I was being duped into thinking it was faster when they just used the animation to make it look faster. Could be me, but I thought it did nothing.
So I have my ATK back on and I couldn't be happier. I guess everyone's different, as if their phones. Some people have the lag, some don't, and some manage their battery well, and other just suck. See what fits you best.