LOL sounds like a sign to me.I was eyeing the DX300 a while ago but is still withholding as it is a considerable investment. The one thing i liked about it apart from its sound quality like the DX160 is the outputs. i like the convenience of having both 2.5 and 4.4. Another gripe is the big size. Now all of. sudden, i cannot find my DX160. I admit that it was not really well accompanied recently but it’s disappearance seems like a call to procure the DX300. Were there any other daps that you considered or this is it?
i was looking at the M3X too to save a couple of hundred bucks but am not sure how well it plays with the HD650.
It IS an investment, but I have found that the best for the money was the DX160. From all the upgrades I have seen on the DX300, it might be the new value to money ratio king. I wanted to see if the newest family member could take it a step further than the DX160. The other DAPs in the iBasso family use different DAC chips. Not that I don't like others, but I knew having the same chips in them, and everything else fixed (comparing to the DX160), I couldn't really go wrong. And I can tell you, this one has better WiFi and BT than my phone (Samsung Note 9), and is at least as fast (CPU-wise).
I hadn't really even considered upgrading, but saw that people were comparing the DX300 to higher dollar TOTL devices such as the R8, and S2000, etc... I don't want to say I bought it totally blindly, but it kinda' was. Only the fact that I knew it had to be (I'd hoped) similar to the DX160, kept me firm in my decision to buy it. I figured that since the DX160 was such a hit for them, they wouldn't change it THAT much (sound-wise), and I was right.
I can't speak for the HD650, but I have some Hifiman planars which are known to be harder to drive than on paper, and HD700 (which is only 150ohms, so maybe it doesn't count). But I also have some TinHifi P1's, which are known to be very hard to drive even though they don't seem to be. I have also read on the DX300 thread that it can drive the HD800(s) very well. As you know, those are pretty hard to drive. The Amp11MKII puts out about 1.2W @32Ohms, and the Amp12 card even more.... I would say that they can be driven very well (depending on if you like the tuning of the device).
Do keep in mind though, that driving planars is actually a bit harder from portable than DD's are. They require more current, not volts (watts).
In the end one has to ask, can you get a better DAP? Probably not, just different at that level. It is going to depend on what's important to your ears (and what bells and whistles you need). If you want to save money, you might want to check out the R6 family. I don't think there is a more value per dollar DAP out there atm, though I can see that someone will try and outdo iBasso soon.
Maybe it might warrant waiting to see what comes out next? I DO know that iBasso is working on a tube amp card for the DX300, if you are into that sort of thing (I know I will have to have one at some point lol).