Well here is the one who tried it.
Got an iphone 4S and an ipod touch 4G, and now i'm using iOS 6.0 on both the devices.
As you know iOS 5.1.1 was really laggy on ipod touch (i noticed that too 😟), i couldn't even search on safari experiencing the same issue: laggy keyboard, if you dare to write on it quickly then safari crashes. Other things like laggy music, even laggy power/hold button (the click is heard 1-2 seconds after?!?), just everything laggy.
This is a bad problem because it keeps getting worse the more you fill your ipod touch with things (you've a 32 GB so you'll experience it from 16-20 gb to the last ones, i've a 64 gb!! so i always have at least half filled, and 100% laggy ahah).
At the moment i'm putting music and some apps on my ipod touch to test it, because as far as i remember even ios 5.1.1 was not laggy at the very beginning of the life of my ipod, which is now fresh from restore. I'll test it when it has at least 30 gb filled, because before i have no reason to test it because i'll never have in my life a blank ipod touch on my hand.
Here's my response, gradually filling the ipod touch and comparing it with ios 5.1.1 on every step:
- blank ipod touch - 5.1.1 running smooth - 6.0 running smooth
- filling ipod touch (on it at the moment 4 gb of music + actively downloading apps) - 5.1.1 already laggy - ios6 LOL i'm sorry to say that it's running smoothly but appstore has already crashed 3 times as i write ahah
-ipod touch partly filled - 18,08 gb of music + 1,15 of apps + 0,80 of photo and other (i think other considers the iOS too because it's already 1 gb after the restore which i did almost 2 hours ago) - (the contenute is a bit below the normal i always carry with me) already laggy on ios 6 (and you already know on 5.1.1, lag as... you know that).
Well i've tested it using 3 apps on the background which a person normally use, just to give the device a bit of stress. The apps are: safari, music and settings, to me happens to have randomly 2/3 of them always open with other apps too on iphone 4S (which always goes smooth, i've 4s 32 gigs and i've only experienced lag once with it on a travel because i took 8 gigs of photos/videos, 2 mbs of free space, and i accepted that anyways since it's still a beautiful device even if compared to iphone 5 (and that's an huge stress!).
Ok so it's a weird lag because the ios itself goes rather better than 5.1.1, just some apps are really bad on ipod touch 4g. I've experienced huge lags on the new interface of App Store, but for example trying to write things on safari at the moment is waaaaay better than 5.1.1, there is no lag compared to that!
With a bit of more stress (facebook music safari maps settings skype and buggy appstore on the background), it still goes smoothly. It's weird because you can feel that the system is really huge but it doesn't lag. I event tried the click test (if we can call it so) to see the lag between the monitor shutdown and the click of the power/hold button, and there was none. Even no lag when you skip songs. But really, on my ipod touch 4g the app store isn't working good, it's laggy in any tab, and when i go to search some app (this is the most important function of the app store, the research form!!) it crashes 7/10 times. The only app which crashed till now is the app store. For the rest, until i fill it for good i cannot say anything more, but at the moment i prefer it to 5.1.1 since when i say that the app store is the only buggy thing till now i'm serious, the rest is better, and not buggy.
Needless to say it's not as smooth as the ios 4 but it's for obvious reasons, let me say that this ipod touch 4g has been made with poor hardware compared to the technololgy of the software, even in the year it has been released (it's not that old).
Anyways as a final thought i suggest the ios 6 since i really think that 5.1.1 is a dead end for ipod touch 4g. the ios goes way smoother, has a bit of more functions (the app maps is a bit better compared to the old, and even lighter), but let's not talk about it since seriously these are minor updates and i do not consider this a new iOS for the ipod touch. And the last good thing is, that to get just a bit better on ios 5.1.1 i had to deactivate some services like localization, notify center etc.etc. here i don't feel like i need to do that, because as i stated the os itself is better than the previous one.
Sorry for my english, i'm italian, and for the wall of words i've written, if you're bored to read then read the last part, I just wanted to try to do a full review =P