It's surprising how several reviewers prefer the U12T to the U18T. Crinacle is the one obvious reviewer with that preference, but when googling "U12T vs U18T" I found others making the same statement. The response graphs between the two IEMs don't look wildly different, though apparently the U18T are harder to drive? And similarly, Crinacle and some others seem to prefer the Trio to the Fourte. Though I'm tempted to buy the "best", figuring I'd second guess later, but "more" (in terms of price and drivers) isn't necessarily better. I don't have a strong preference between dynamic or BA bass drivers; I've heard both done well.