Of the four I kept the IdeaPlay for myself and gave the Hiearcool L2 to my wife. At the time I made some notes about each pair. These are my notes:
Most important to me were sound quality, comfort and noise cancellation. The IdeaPlay sound quality was extremely good (probably not as good as top tier Bose, Sony, et.al., but quite good overall) It is a little bass heavy, but clean sounding. Mids and highs are very clear. Overall the sound is well balanced. Of the four headphones I bought, this pair is the only one that the sound was exactly the same whether the ANC was on or off. The others all sounded different depending upon whether the ANC was on or off. The sound on the IdeaPlay was also the same whether using Bluetooth or the cable. It has more volume using BT. These get loud! Comfort is the best of the bunch, followed closely by the Hiearcool. The ear holes are 2.4x1.5 inches and rectangular (not round or oval). They weigh 11 oz. The noise cancelling on the IdeaPlay is not as strong as on the others, but still reasonably good. I use these headphones when using the lawnmower or especially the leaf blower and will use them on the plane if I travel again and they are good for long time periods and block droning sounds well. The controls are pretty logical and better than on the other three pair. I have also found they are very good for phone calls. The other person on the call does not know I am using a headphone and they are very clear to me. Finally, I have downloaded an equalizer program (Equalizer APO) to my desktop (Windows 10) which allows tremendous customization of the sound. With that program engaged these headphones sound incredible. I just need to find the same program for my phone (Android). This program would probably overcome the deficiencies in any headphone.
The Hiearcool L2 was fairly comfortable, with cushy large earpieces. Sound was generally very good, though a little bass heavy but not muddy or boomy. Mids and highs come through pretty well although the bass is stronger. These sound better with the ANC on. The sound field broadens, it gets a little louder and bass gets even heavier but still clean. Mediocre controls - most of the buttons feel the same to your finger tips. The upper volume button turns the volume down (goofy). ANC is good - I only tested them by cranking up the home stereo and not with a leaf blower or on a plane. They weigh between 10.5 and 11 ounces.
The Cowin headphones had thumpy bass (worse than the two above but better than the next) but the sound is very affected by the ANC. With ANC on is sounds much better. Voices are pretty clear, so are cymbals. It was very musical and sounded a lot like my home stereo (lots of old Harman Kardon and B&W) which is a good thing. Overall a good sound with ANC on and easy to live with. However, this headphone has to have the ANC on all the time for decent sound. Controls are stupid - the top button turns the volume down. Also you have to press and hold the volume button to turn it up/down so it is easy to turn it up/down too much. I could not get the ANC to work when using the wired cable - it cut off every time. Remember where I said the sound quality was good only when ANC was on? If you've got a long flight be sure you charge the battery in advance because you don't want to listen to this headphone while wired (sound quality suffers) and the ANC wouldn't work. Not as comfortable as the first two. A bit heavier and the ear cups are firmer. They noticeably pressed on my glasses. Overall the Cowin had very good sound quality with the ANC on and the ANC was also good. Two strikes are the illogical controls and the uncomfortable fit.
Finally, the PAWW phones were the worst of the bunch and the most expensive. The bass was thumpy and became worse with ANC on. Mids were hard to hear. With ANC on the sound field made you think a switch was set to Mono and not Stereo. ANC would be usable only if you were not listening to any music. The controls were logical and the earpieces were more comfortable than the Cowin. Between the highest price and the poor sound quality of music with ANC on, I quickly took these out of consideration.
One final note - recently I saw a pair of Sony headphones (WH-CH700N) on sale at Best Buy and bought them on impulse. They were about $120. I was completely underwhelmed by the sound and could not get them to sound good no matter what I listened to. There is a dedicated app you can download to your iPhone (I was unsure of whether I could download it to my Windows or Android stuff) that might make it better but I just couldn't see the point of having to do that to get it to sound okay. As it stood right out of the box I had no interest in them and quickly sent them back. I would buy the IdeaPlay every time over the Sony. And probably the Hiearcool over the Sony too. Both of them sound good right out of the box, have no fatal flaws and beat the Sony on price too.