Sound quality and distance is really good on this product. Have not use it longer than 1 hour every time just used for speeches during dinner. I most have used outdoor and range is good as well about 50 feet away still sounds clear. Must be out in open on mixer can't be in a box where receiver does not see transmitter. Have used on mixer or in back of powered speakers and work very well. Great to have in your bag as a back up mic as well. Connects to any mic and makes it wireless. No need for cables always a plus.

I tested it at home first on my Bose PA using Shure SM58 mic and a Seinhesser XS1 mic. They worked perfect! Then I went to an Open Mic OUTDOORS and it was STILL perfect. Sound was exactly the same as being plugged in. WOW!!! Thanks! Yes, you DO have to watch the buttons which will turn on when you pack them up, but if you put them in the box afterwards, you will avoid this problem. Thanks again Kliq!

I just did a 2+ hr private gig with my Acoustic Electric and mics. Both the XLR and TRS versions performed flawlessly. Not one dropout was observed. Sound quality for the price was outstanding, using Sennheiser E835 dynamic mic.
I own 2 of each and hooked up all 4 (4 channels is max) for testing and all 4 connected great...~$350 4 channel wireless system..you cannot beat that.

Issues/Recommendations:
One issue I found is that the power buttons are a bit "exposed", they are slightly raised above the body, and when these are together in a bag/pouch there is a tendency for the ON button to get pressed for long duration and have the unit power up. Then it sits...and eats up the battery. One design improvement would have been either a sliding power button or recessed power button to prevent accidental power up. I am thinking of glueing a small "guard rail" next to the buttons to improve on that or shave down the ON button to be flush with body surface.

The other issue is that you will find XLRs are un-shielded internally, only 2 wires (pos/neg) are connected with shield pin not wire to the internal board. Whereas this is not a huge issue for very small run (about 1 inch wires), this may be an issue when using the RX (Receiver unit) with a XLR cable to the input mixer/amp, rather than direct. I did have a hint of noise when checking them out - this may be the source in a interference noisy environment. Will see if adding shielding to the internal cables and terminating them somewhere will improve anything.

Time will tell quality and longevity but for the price, pretty good execution!

Units are bulky: not a deal killer
Units worked well on my Beringer Mixer
Can't jam 2 receivers into adjacent XLR jacks; leave an empty XLR between receivers.
Comment: How many wireless mics are you gonna run?
Unit is awkward hanging off the side of my journo cam.

After being disappointed with several different brands this one finally does the job EXCEPT the battery life is very poor. I get ~2 hours on a charge. Other than that these are great. Noiseless and absolutely no delay. Great range also. These would a no brainer five* if it wasn't for the battery issue. Comes with a really nice hard case, too. Oh, yes! They work perfectly with my Alembic bass with active electronics. Something none of the other brands at this price point did.