I've just ordered this, so my review is a first impression, I can't yet speak about its long term use.
Regardless, It has impressed me!
Visuals: The product looks very good, much more appealing than a simple glass or plastic container. The lid and connecting formicaruim are very interesting to look at and have a lot of character over the usual square ones found online. The red glass covers are a nice addition to the formicaruim, allowing for easy viewing of the ants while not disturbing them too much.
Dimensions: these are as described but the measurements of the outworld seem to be excluding the lid and connecting ports. So it's a few cm bigger than advertised, but no complaints there!
(I've put a British £2 coin in the photo for scale)
Quality: the build appears strong and durable, the connections / lid fit very snuggly, a perfect match and it feels like good quality when handling it.
Longevity: as previously stated, this is just a first impression but I really like their additional port on the other side of the outworld which would make adding more formicaruims and outworlds easy. They also have different adaptors, one that is direct to their existing products and also a pipe connector so you can add their products to something else if needed.
Postage and communication from the seller: Excellent on both accounts. I was aware of when my package had set off and was sent tracking info. It arrived slightly earlier than expected too. The product arrived well wrapped and in excellent condition.
Cons: the opening into the outworld is a little small, so I had to use tweezers to decorate and I will have to do the same with feeding the ants. Not to worry though as the additional feeding tray supplied comes with a convenient long handle for easier access. I'm not 100% sure how easy it would be if I had to clean inside the outworld, again I presume tweezers would be needed.
I'm a little worried about disturbing the ants by opening the ports on the formicaruim to add water. Though these are easy enough to open and a very nice touch. If I were being really picky I would have had a small hole in the top of them to put water in via a syringe. It would have been a nice touch, but regardless, I love the easy access idea and ability to replace the sponge if needed.
Overall: a brilliant product, I would highly recommend it. I'm very happy with all the major aspects of this and I will be happy to purchase from ant keepers again in the future.
Please note: The decorations inside the outworld in the photo are my own and the photo was taken just prior to adding the ants.