Best "Portable" DAC? Oppo, JDS Labs, Audioquest Dragonfly, others?

I’ve narrowed it down to these possibilities for a portable DAC to use direct with my iPhone:
Oppo HA-2
Oppo HA-2SE
JDS Labs Standalone DAC (w/ RCA option)
Audioquest Dragonfly Black or Red

If anyone has any to add, please go for it. I’m using an old iPhone 5 for music playback via Apple Music into my 2-channel stereo. I’ve deleted everything I can off the phone. Also, since there is no phone plan connected to this phone anymore, I’ve turned off every function I can, except WiFi (so I can use Apple Music). I also have it in Airplane Mode and Do Not Disturb (not certain if any benefits there or not). My current connection is via the Apple A/V Composite Cable. System consists of a Creek 4330SE integrated, Micromega Stage 3 CDP and Vandersteen 2C speakers.

Anyone have experience with all of these DACs? As for price, The cheapest of the line-up is the Black at $100, then the ODAC at $175 shipped, the Red at $200, and the most expensive being the Oppo at $300 for the HA-2SE. I rarely use headphones. When I do, it’s when I’m on a beach or sometime when mowing the lawn.

Wow! Both the ADL X1 and 2MTech have great reviews. Which is better of the two?  
I don't read reviews so I can't say. I linked them to Cable Company because they will send you demo units of both dac's to try first. Personally, I like Furutech, but you may prefer something else.
As I read more about these DACs, it seems that they are most beneficial when using high resolution files. What is classified as a high resolution file? Since I'm using Apple Music as my source, and their files are AAC 256kbps, am I going to hear any benefits to getting a DAC anyway? I can see these DACs being great if you have a good source to start with, but with the Apple Music files being so low to being with, what's the benefit of adding a DAC? They can take a garbage source and make it CD quality, can they? 
" They can take a garbage source and make it CD quality, can they? "
No, and don't let anyone tell you different (some people will actually try to argue that.). MP-3 is lossy. When you rip a CD to MP-3 files, information is lost in the process, and you can't get it back. Not to be confused with losless compression like FLAC. The information is compressed to make the file size smaller, but you get it all back when its decoded.

Is it worth getting a dac for MP-3's? Its hard to say. I would pick up a Dragonfly from Best Buy and try it. It can always be returned. If your files were CD quality (16/44) and above, then yess, a dac would be a sensable upgrade.

Hi Roscoeiii, 
Since posting my initial question, I've been continuing my research. Yes, the Mojo Chord is another one I've read is very nice.
I've also been reading that the Meridian Explorer and Director are very nice, but are not iPhone/iPod/iPad direct compatible.  

Hi mb1audio02, 
Since I'm using Apple Music via iPhone 5, and since their file size is 256kbps (therefore doesn't even register a bit depth and bit rate) I'm gonna take your advice and try a Dragonfly first and see if there any improvement. If I don't notice any improvement there, then there's no point in going any further. I'll post back once received and reviewed. 

Thanks to everyone for all the info/comments/advice. 
I just discovered iDevices (iphone/ipad/ipod) accept a maximum sample rate of 48khz. Which means anything above that is a waste for the purposes of connecting an iphone to my stereo. I also picked up a used HRT iStreamer since this device was made solely for use with iDevices, and it's max sampling rate is 48khz. I will compare with the Dragonfly Black (now on it's way) and sell/return the loser.