I have the lunchbox and love it for its quirky looks. I transport it in a soft case for the 2 shows we do a month. Lightweight and small.
If I was playing out more often and carting it to and from rehearsals etc I'd probably go the rack version (with a small rack obviously) for no other reason than sturdiness and piece of mind. My KPA has seen mild abuse during 1am car park band loading - a rack would show its advantages in those moments..
USB port on front is handy on the rack but personally I'm not a fan of the led'less encoders, again, i just like the cosmetic quirkiness of the lunchbox.
Lunchbox looks cooler 
i got both and i prefer the toaster for editing due to the led displays,just seems more comfortable and quicker,but i plan on using the rack for live stuff.
If you already have a lot of rack gears then you should go for the rack version, but if it's not the case you should go for the lunch box! Cool look, easy to carry and easy to use!
Lunchbox for me plus flightcase for transport. Best of both worlds, sturdy and easily accessible.
Thanks for the responses guys.
My main use for KPA is going to be gigging/live shows.
I'm on the fence with the look of the lunchbox. Wish I could see one in person first but I do like the look of the LEDs
I was uncertain, initially; but since there was no rack unit when I bought mine, I just went with it.
Now, I'm so glad that there wasn't another choice. If the rack unit had been around then, I might have gone for the more *pro* looking rack....that would have been a mistake (for me). The toaster is just right. It's easily portable, and has room in the back to hold my GCP power supply and midi cable. I've gotten past the looks, to the point where I actually like it now.
Of course, there is the fact that the rack isn't available in the always classic white... 
None more vintage. 
BTW, in all seriousness, the white IMO is easier to see on dimly lit stages...better contrast between the lettering and the background.....
....and it's more vintage! 
I went with the lunchbox out of "necessity" (rack not available when I ordered) but I am rationalizing that it was a good idea........I will post some pics soon in a dedicated thread but my lunchbox KPA rig will be a more compact, less weight and yet every bit as capable unit as my Axe rack....
I have the rack now, but I had the lunchbox for a year prior to that. I miss the LED lights around the knobs, but I like the USB port in the front with the rack. I have an AXE II also and they look great paired together in my studio desk. Neat and tidy.
I will miss the lunchbox form factor when I go on vacations though!
I waited a long time for the rack-version, but eventually ended up ordering the luchbox. The missing LEDs changed my mind. It is much easier to read the status of certain things with the LED rings around the controls in the often dark environment on a stage. If I still want it rack-mounted the lunchbox will fit on a shelf in 4U, so my entire rig including the KPA, wireless receiver, personal monitoring mixer and IEM-transmitter will fit in a shallow 6U rack. That's still a very compact rig. I just wish the luchbox had threaded holes in each corner at the bottom. That would make it very easy to secure the box to a rack-shelf. The same threaded holes could also be used to mount some sturdy rubber feet on standalone units.
I have the rack now, but I had the lunchbox for a year prior to that. I miss the LED lights around the knobs, but I like the USB port in the front with the rack. I have an AXE II also and they look great paired together in my studio desk. Neat and tidy.
I will miss the lunchbox form factor when I go on vacations though!
I prefer the lunchbox/radio design, it's less bulky, has more knobs and a very cool personal retro design that makes it stand out compared to all other gear.
But I must say that the kemper rack is pretty nice looking too and well designed.
Too bad that the led lights components didn't fit in the 3u rack design.
A tip for those that want the kemper lunchbox usb connection in the front is to simply connect a usb extension chord so the usb stick easy can connect in the front.
Hey phel,
Curious here, I have the lunchbox version of the KPA and would also (eventually) like to fit it in a shallow rack. Question : are you positive the lunchbox will fit in a 4U rack?
For some reason I was under the impression I needed at least 5U...
Regards
bigb6611: you're right. The luchbox' height of 21.4cm does require 5U. I did my measurements on a custom-built rack that originally was equipped with a power-supply and thus 3/4U higher than a normal 6U unit.
bigb6611: you're right. The luchbox' height of 21.4cm does require 5U. I did my measurements on a custom-built rack that originally was equipped with a power-supply and thus 3/4U higher than a normal 6U unit.
hey man , would you share a picture of your rack ? i'm planning to get a custom rack too for the Kemper ( i have the lunchbox too )+ other rack units .. Thanks !
I can see the LEDs as being a good feature on a dimly lit stage but I would hope to have all my parameters in order before playing out with it. Still, not sold on either design being better than the other.
Still saving and will see what's available when I'm buying one. 
I think it would be easier to take the lunchbox onboard a plane as carry on luggage. Not so easy with the rack. I guess it's a toss up whether you want to hand carry your guitar or your Kemper.
I would have gotten a rack version when I bought mine, but I'm glad they didn't exist back then. I prefer the convenience of the lunchbox.
My rackmount gear has always tended to stay packed between gigs. I usually ended up buying two of anything I wanted to use at gigs and for recording.
The lunchbox is easier to move around than a guitar
