Can confirm, I've had a fellow jade enthusiast buy from JadeiteRoom after scouring for some dragon pendants in a nice green color who was willing to buy from her despite it being overpriced (in my opinion) and him knowing that she's known to suddenly raise the price. JadeiteRoom does do certification upon being paid a certain amount for it to HKJSL ($40 I think?) so maybe consider her as last option if you really want to buy a lavender bangle ASAP.
I'm sorry but this kind of irks me when you put it that way. While it's true that nowadays jadeite treatments have become alot more sophisticated than it was back in 1980s, this shouldn't be the reason why you completely disregard a seller's hard work + potential profit just because of vagueness + how labs may not be able to catch advanced treatment on a piece of jade (boulder/rough), especially since those types of treatments may cost just as much as the jade boulder itself and it meant to imitate the highest quality of jade bangles/carvings (icy, high icy, glassy quality)
Maybe this is just me being wishful thinking and trying to see both sides of the argument, but I think if you aren't willing to buy jade (or jewelry in general) online knowing there's a small chance you may end up with a treated piece + shelled up lots of money as a result, then perhaps just move on to another seller you find yourself trusting with instead of unintentionally slandering a seller for selling finished products that are treated w/o knowing. This specifically is the reason why sellers almost always offer a full refund + maybe some sort of compensation if you do have some other reputable labs test the piece and is confirmed to be treated as well.
This is why we often dm/pm these sellers for specific information regarding their pieces whenever a listing description doesn't cut it. Allan Spehar's products from as far as I can remember is due to him putting most of his time trying to find rare nephrite pieces (Wyoming Black, Big Sur, Dianite [not truly nephrite but has similar properties], unique nephrites from various places f.e.), and some nice Guatemalan Jadeite pieces, alongside labor costs.
Churk's piece from how I personally see it, is fairly priced cause most of these pieces are what the Chinese people call it, dry bean species, or glutinous species, in which the jade is very coarse in texture and it's structure is visible to the point of looking sugary with light transmission being able to pass through it barely at times. Some pieces I do agree are lower priced to the point it seems like a bargain (for example, his baby bangles, and other bracelets) but this is because those types of jade are either/or lacking in color (jade is naturally white in color, so it needs other mineral intrusions to give it color), is really small in size, has color but lacks transparency/fine texture, and/or is mass produced so Churk has some leftover from his inventory.
In regards to UJ listing most of their pieces as translucent despite some of them looking opaque in texture, most sellers do this so long light can transmit through the piece and reveal it's structure.