We all have lives, reviewing is not my job, I have a full time job, family, kids, and other outside projects. I'm just making an observation that in the last few years, you asked a lot of rapid questions, starting a discussion in Westone and other threads, people spend their time replying back, and you never acknowledge it. But, that's fine.
Of course, I'm a reviewer, and my review is my opinion. I'm actually a Contributor on Head-fi with hundreds of published reviews,
here, and close to 21,000 (!!!) likes based on my contributions of helping Head-fi members who trust my opinion and appreciate my help, just like manufacturers who trust my opinion and send me review samples. I'm not writing here "omg, Westone is the best IEM in the world" lol!!!, I'm just sharing my opinion about how these sound and compare based on my OWN personal experience of using them and measuring their Frequency Response which is not identical.
You made a statement that a manufacturer told you they sound identical. You didn't hear old vs new UM Pro 50 yourself. Are you saying you personally called Westone in Colorado (US) and they told you this over the phone? You are making a bold statement, so please back it up. The only thing I'm aware of that someone from Westone customer service mentioned over the phone to someone else that drivers are the same, shells have changed, and the sound should be the same. That was the only post someone shared in this thread last year, and after further discussion, Westone no longer makes this statement.
So, did you recently call Westone USA office in Colorado? Did you talk to Karl Cartwright who designed and tuned them? You don't have to agree with how I hear or describe the sound, you are entitled to your own opinion which I respect. But you are attacking me, saying that my opinion can't be trusted because Westone told you something else. I talk to many manufacturers and their sound designers every month, including Westone, and never heard them mention about UM Pro 50 having the same sound. So, I'm curious, what is the source of your information? Please share.