I'll give you some examples: I had purchased the iBasso DX200. I have never been able to listen to it with pleasure, beyond all the possible configurations both with different ems and with alternating cables. And I sold it after about ten days. I own the Kann. Obviously in terms of amplification and sound quality M3X pays the Kann duty, but for example I have noticed that M3X makes low quality mp3s sound better (compared to Kann). While with the Kann the thick mp3 reveals many more defects and background hisses. I own Dethonray DTR1. Sound different from M3X (which then may like more one or the other is a different speech) but while the Prelude has a more open and clear sound, M3X has a great body and a very pleasant warmth with certain types of musical genres. Let's leave aside the multimedia and connective part because M3X is in front of the DTR1 light years, as the Dethonray Prelude I use it ONLY for simple listening with the micro sd card.
The Kann for example on metal, hardcore, sludge songs, loses a little detail. M3X on the other hand does not have the same speed, but precisely for this reason the notes do not end up on top of each other and everything remains pleasantly in line with the audibility and purity (pass me the term) of such compressed musical genres. the Kann costs 900/1000 euros. The Dx200 costs around 600 euros and the DTR1 Prelude around 600 $ .......
Obviously if you listen to Flac or DSD with the Kann, the quality and silence are better than with M3X.
But speaking a lot in general, even assuming that all three daps I mentioned (Kann. DX200, and DTR1 Prelude) are in some ways better than M3X (but in some cases it isn't) anyway the price difference in terms of pure musical quality, it is not entirely corresponding to listening. But this more generally then depends on countless factors: Advertising, steps of the same brand, investment that has been made on the dap, innovations introduced in terms of engineering, materials, solutions .... etc. You enter a field so vast and remote that it is difficult to get out of it.
But if in a hypothetical test in the dark I had to qualify the price difference (for example) between M3X and Kann it certainly does not equal a difference of $ 340 against $ 1100.