So I have a few spare minutes and want to let you know how I found this case.
First off, it arrived promptly, which is nice. Two days after payment, which means it was posted ASAP after payment and delivered by 2nd Class post. Free postage is also a decent thing - the cost was £35, flat.
So size wise it's about twice that of a GW case, maybe a little less.
Looking at the exterior, there was a little bit of creasing in the cardboard - exclusively in the lid, which is natural since it's the only part that moves.
Obviously at the moment this is minor, and only time will tell if it becomes an actual problem or not. I will note at this stage that the cardboard is not as rigid or solid as the KR Multicase cardboard, which is significantly denser, and therefore presumably more resistant to things like rain.
Opening the case, there was a fun size packet of Haribo, which was nice, and hasn't biased my review in any way... ;)
Looking at the foam, you certainly get a lot of it! The case holds 448 models, which is something on the order of quadruple the regular GW case capacity. It'd certainly do well for people who enjoy things like collecting Companies of Marines, or you could easily add the sheets to other cases for more infantry-dense armies. I know a lot of my cases are mixed up layers of KR, Battlefoam, GW and so on depending on the army and system.
With regards to the foam itself, it does the job very nicely. It's kind of a halfway house between KR and Battlefoam in terms of rigidity, it's also stronger than GW foam. The foam is glued quite strongly (pretty much the most strongly glued I've come across) to the base along the horizontal lines, the vertical lines are unglued. Obviously if you want to cut them up for models then you want to go vertical, which is favourable for back banners and bikes, but less good for wide models like Terminators.
The slots themselves are pretty much the perfect depth, holding models with swords etc deeply enough to make risk of damage from blades sticking out negligible. It's also slightly accomodating with height - Marines with bigger backpacks should just about fit in neatly. The larger slots along the base are actually an invention that is more useful than you first think - they hold things like Sang Guard (which are actually rather large compared to normal slots) in enough numbers to mean you don't need to chop up the case as much as you otherwise might. Also makes it easier to find special/heavy weapon troopers or Sergeants if that's something you struggle with (Imperial Guard, for example).
Overall, I think this case is great for storing models and taking them to the local workshop. It seems solid enough for most use, but I do have reserves about taking it outside when it's absolutely BELTING it down. Drizzle etc should be fine, but I don't want to risk an actual downpore.
Finally, there is nowhere, absolutely nowhere else, that will let you case up and store almost 450 models for £35. Not a chance. So on that basis alone, even if you use the trays in other cases, it's very good value for money, because the foam quality is superb.