I have both these cages and there are pros and cons to both. I would attach links to threads where I have pictures but they're mostly on Photobucket so that's no good. I like them both a lot.
As the duna multy is plastic, it doesn't weigh as much so easier to clean than a glass tank, I've found. The lid is nice and secure. As it's a tank you can have the bedding as deep as you want but the base is deep enough that filling that up still leaves the clear section to see in clearly. It works out a bit smaller than the terry due to the sloping sides but not by much. Is deep enough for an 8" wheel but not a 12". I found you need to have it against a wall when you open it so the lid can rest against something or it pops out of he hinge bits. And hanging anything is a pain as the whole grilled section lifts up so much more than a seed stick swings everywhere. The water bottle can be a bit of a fiddle if ou don't have a holder with suckers - there are holes in the top of the plastic lid you could wire into but it means having the bottle on the "wrong" side so it would be against the wall. I use a drinky bottle with suction holder that I have spare so it's no bother. Of course, you don't have to use the gap that's there at all and use a free standing holder instead but. A tank bottle holder wouldn't work as the metal lid is inset. But these are all minor grumbles.
The kerry has the benefit of not losing floor space as it's straight sided and I like the little ventilation strip on the back. You can hang a couple of things if you want as the opening bit isn't the whole lid. Can be a bit clangy when you open and close it though. As the whole lid slides on and off, you need to check there are no gaps if you had anything near the top the ham could reach. I doubt a ham could push it past itself though. There's no natural space for a water bottle (as you'd expect from a tank) but I have one of those metal holders that hooks over. It's a bit deeper than the multy so good if you want to do something more with a little level (you could in the multy but this would give you more height to play with). Good for deep substrate. The main downsides are the price and the weight. It weighs a tonne - I can't lift it myself. So cleaning is more of a scoop and wipe affair (maybe even a hoover) unlike the duna which I just take the top off and tip the tray into a bin bag. For the kerry I use a big dog food scoop! A timid hamster may feel a it exposed as the cage is deeper and there isn't the plastic base to hide behind.
I think that's all I can think of for now. Any questions, just ask!
