Great comparison, thanks for taking the time to make that. First listen on my phone speaker, the 434 sounded like it had a lot more midrange presence and clarity, and I preferred it. Second listen in decent headphones, the 434 sounded like it had an overly boomy low end and the 1025X tighter and more balanced, and I ended up preferring the 1025X (which I have!). Will check it on good speakers next!
Here's a another comparison, this time against the 735: