I'm just going to say that if you're coming from another high end device, you're going to feel some lag. I just got the tablet and at least for me, I feel robbed. I just paid $500 for laggy software and I've had 3 random crashes in 2 days of use.
Compared to high-end S-800 phones with 5"ish displays, yes, the N10.1-14's transitions occasionally aren't as smooth. Compared to other high-end Android tablets, what in your view is faster? Multi View and S Pen have a ton of open processes constantly running in the background anticipating their use. So if you want "fast" strip out all the N10.1-14's features and run AOSP/AOKP on it. Personally, the sole reason I bought the N10.1-14 was because of its productivity features and what I can do with it that you can't do on any other tablet so if I have to put up with some transition lag so be it. As for "crashes" I've got 144 apps, 9 full time syncs, and 21 widgets running and have never experienced a crash, FC, or any other type of OS anomaly since October. I take that back. Initially I was using the Trip Advisor wallpaper on the lock screen and it would cause TW to reboot every other day. Once I stopped using it everything was fine.
Heh - that's what I am hearing/reading a lot of and which is making me so hesitant. The device itself has great specs and should perform amazingly, but as we know, a device is also only as good as it's software and many people are saying the stock ROM/software is very buggy and laggy and does exactly what you are saying.
95% of the time, and 100% of the time within a single app, there's no lag. When a bunch of stuff is going in the background you'll occasionally get a millisecond long stutter in a transition or app opening/closing. You'll also get the occasional "spinning wheel" when doing something resource intensive like capturing a full screen of content from a third party app via Air Command and moving it to Scrap Booker. I'm not even on the latest ROM (I'm on MJ4) because I have a 3G N10.1-14 and people in the U.S. have said MJ9 improved fluidity more than what I'm experiencing. There are aspects of the UI that are "odd" because a phone UI on a 10" display is a bit bizarre having nothing to do with specific h/w or s/w. But, again, I've had no OS, UI, or app issues since October so the s/w is definitely not "buggy." And I have additional radios, antennas, and s/w being 3G that add even more burden to the s/w and h/w.
Here's a vid of my N10.1-14 moving through home screens. My N3 on an official KitKat build that's running the same 144 apps is next to it for comparison. At the end I pinch zoom to display all the home pages. That is without question
the worst lag you'll ever see on the N10.1-14. And it's 10 times worse than the millisecond long stutter you'll occasionally see in transitions.
If people are experiencing worse than that or constant lag I'd suggest they look at the apps they have installed, their configuration/settings, and what apps/processes they have removed/frozen/turned off. The latter is especially significant because as nested and inter-dependent as all Samsung's add-on s/w has become it's easy to disable something another app's dependent on and not know it. For example, disabling My Magazine on a device causes huge battery drain on the Galaxy Gear and issues with Gear Manager even though there's no logical reason one should be affected by the other. I'm running bone stock, have every gimmick Samsung's s/w provides turned on, am using an earlier less fluid ROM than some, and have an enormous amount of apps, syncs, and widgets running. I'm a prime candidate for "lag" and don't experience any 95% of the time. So if someone's experiencing worse than I am I'd suggest they examine what
they've done to their device.
P.S. - Being 3G, my N10.1-14 is always connected to the Internet so whenever I turn it on it's always sync'd. Since most here have Wi-Fi versions here's something I've noticed. When I turn my N10.1-14 on for the first time, like after getting off a plane, and it connects to the Internet for the first time it can be painfully slow (and laggy) for as long as 15 minutes while every app and process that needs Internet access updates itself. I'd guess the same thing would happen with a Wi-Fi N10.1-14 even if it was left on but re-connected to the Internet after being offline. So there's "lag" and "situational lag." Both my N3 and N10.1-14 are the slowest devices I've ever owned when it comes to being fully usable after a reboot or going online after being offline.