hi, i just joined the site in hopes that someone will eventually figure out what the problem is. i *definitely* have lag - it is not even close to a matter of perspective or opinion. like others have said, it's not all the time, but it was way past the point where it becomes annoying, especially on a freaking dual-core. sometimes i wish i still had my samsung rogue rather than this thing. that's how bad it gets. i have uninstalled various apps, tried various settings, though i am not an expert. i would take video of it but i'm not sure i have to anything to take video with except the phone itself. i suspect that a good number of people are having the same experience as me- lag far beyond what anyone would call a subjective opinion. like some have said already, sometimes it's just 3-4 seconds, other times it seems like 30 but it's probably 10 or so.
my RAM usage does appear pretty high - often about 85%, even when I'm not running apps in the background except things like swiftkey or avast. avast is only using 0% of CPU and 8 MB of RAM according to Zapper Task Killer - though weirdly my CPU usage is jumping up and down as I watch it - from 5% up to as high as 60-something % , with no app using more than a couple %, ie, not nearly 60% being accounted for. also, this happened when i had outlook antivirus previously.
some have found that the "setting storage" app or process uses more and more RAM the longer the phone is on... mine seems to do that but i'm not sure that accounts for all the lag. i have a calendar widget, a google reader widget, a weather widget, and a notepad widget running. but these don't seem to be the problem, at least they're not showing up as using a lot of RAM or CPU as far as I can see.