Normally I would never review a single upstream component since there is just too many variables within the chain to affect the overall sound quality.  The two units in question on the other hand are pretty much all in one approach, both were crowd-funded and similarly priced and both claim to be the best of the best in their niche. 
   
   Most are already familiar with Geek Out so I won't say much of it's build quality and design. Couple of things stood out for me though:
1. flimsy volume buttons (to the point of having a feel of being broken)
2. lack of proper indication of it's functions and controls. I understand the priority for better sound quality that came with the latest firmware update and messed up all the original controls and indicators. I personally would probably try and do things different without sacrificing ease of use and aesthetics but this is a minor thing and once figured out becomes a non issue.
   
   Pono looks and feels cheap and all despite being a limited signature edition. One would easily mistake it for a toy, really. It's pretty bulky for what it is and not so comfortable in use, both UI and screen/button layout and functionality vise. Durability is very questionable with all plastic construction and poly-carbonate screen. Storage capacity and expandability is good if not great (the slowest available micro SD card was included in the package).
   
   Before I start with sound quality assessments please note I am using fairly unique and very efficient planar-magnetic headphones heavily modified in order to have extremely linear frequency response, pretty much ideal phase/impedance characteristics and very good distortion ratings to boot. Basically because of the above fact I feel this review may not be all that valuable and should be taken with a grain of salt simply because most other headsets present either screwed up frequency response or are a difficult load or both. Also note I am judging without any adjustments for the price/size/market niche/crowd-funded nature etc.
 
   Sound:
 Both units are fairly similar only in one thing, nothing with their sound quality is popping out as being terribly wrong and that is what's most important for me with these units. Sound-vise both I would consider to be a very good buy right from the start but similarities pretty much end for me right there.
   
   Pono sounds overly soft and surprisingly it is valid throughout the entire frequency range. I suspect many will like that, especially those who adore all tube, vinyl and overall fatigue free listening experience above all. I personally see some problems that come with such softness:
1. Vocals sound kind of whisperish, lacking body weight.
2. Piano notes lack weight too, like every key isn't pressed fully and hard as it should.
3. Low frequency is there along with good extension and control but is kind of fluffy, no bite.
4. Highs are pretty good, fairly resolving and extended just maybe not perfectly well refined.   
  Overall it feels like Pono's amp (sounds funny by the way as it's equivalent to diarrhea in Russian and I feel that's how this player will be nick named there, shame it's a pretty good player;-) is not holding on tight, just lets go the sound too early if this makes any sense.
   Sound stage and imaging are both ok. Nothing really smashed, washed out or all in your head/face and in one place. It isn't deep though and kind of all rounded but nothing too disturbing. I would also prefer it's sound to be further away.
   That's about it, please ask if you feel I missed anything which I am sure I did. Overall this is a good sounding player and will win many hearts. I have not heard many portable players out there but this one to me beats my iPod classic, Note 3, Dragonfly and very different but at first glance is almost on par with the Geek out.
   
   Geek Out:
   First off huge thanks to my good friend Darin Fong for loaning his Geek 720 to me. This unit has the latest firmware and was used in TCM mode attached via Monoprice USB cable to a Lenovo Windows 8.1 running JRiver Media Center-19 using Geek Out HD Audio Kernel Streaming mode (I preferred this mode over direct, wasapi or asio).
   
   Putting it plain and simple Geek out for me personally is a clear winner overall. Even from the usability standpoint. Besides using it with desktop/laptop/tablet one can also hook it up to an android phone and have a great portable media player with sound quality that should be hard to beat (have not done this android thing yet but will try once and if I ever gem my own unit, backed their Geek Wave for now).   
   All the warnings mentioned above still apply as I am comparing it to my own reference sound so take all the rest with a grain of salt.
 
   Sound:
  Once again pretty much nothing stands out as being off and that is a very good thing and a big compliment even if it doesn't look like one.
  Few things were still apparent to me though:
1. Low frequency could be extended a bit more and use more power, be tighter and stronger.
2. Mid-range is good but I would add a bit more softness, in fact I would take some of the excessive softness of Pono and throw it to Geek out for a perfect blend.
3. Highs could be more gentle, smoother with better transition to the mids as right now it's a bit rough, nothing terrible though.
   Sound stage is pretty good; open, well extended, even and fairly resolved. Could be better but probably not by much.
   
   Even though this is a truly portable device and fairly priced to boot so expectations just can't be very high but I personally was very much surprised about it's sound quality. All it's weaknesses are spread out evenly and are not distracting helping geek out to sound very pleasant overall. This makes it a safe bet for an inexpensive but fairly refined sounding device. Not sure this Geek Out is the best thing in portable gear but to me it beats my Firefly with about the same score as that same Firefly beats my laptop's direct headphone output.
   
   One thing is for sure, music lover can have lots of good time listening to either!