I bought a set of BX-5s almost 2yrs ago, right after Leupold dropped the MAP $200 or $250. I had wanted to compare them to a set of Swaro CLS 15x56s, but never got the chance before the price drop. I had ~$250 in Club points on my Cabela's card acct, so IIRC, the BX-5s cost me about $800. And yes, they are made in Japan - it says so right on the front hinge cap between the barrels, and on the box. The bodies are made of 'glass reinforced polymer'.
About 4mo after getting the BX-5s, Athlon announced their Cronus 15x56 binos. I bought a pair to haul to a couple of gun shows to re-sell, and of course had to open the package to compare them to my BX-5s. The optical quality is similar, but I give the edge to the Leupolds, because they seem a little brighter to me. Not much of a comparison, as I've spent hours behind my Leupolds using them to spot/score at a couple of Hi Power prone matches, while I've only done a very basic bit of 'back-and-forth' checks between them & the Cronus binos. I know I can spend long periods of time on the BX-5s with little or no eye fatigue, just haven't put in the time behind the Cronus binos to see how they compare in that regard. Only reason I posted this is because the Athlons are also made in China, and are probably comparable to the Forge binos. They do come in a nice, heavy-duty water-proof padded plastic case, and the body is magnesium, not plastic.
The final comment I have is that I'll not be selling my BX-5s - I have not one single negative thing to say about them. My opinion of China is lower right now than it's been in a long time, but these Cronus 15x56 binos are a pretty decent pair of glasses.