I purchased this converter box on 7/13/17, and on 9/28/17, although there was no power surge in the house, the unit went off and nothing would cause it to turn back on again. I had purchased the associated 3-year warranty, but when I went to that company's website, I received an automated message that the unit was still under its original manufacturer's warranty, so I needed to go to the manufacturer. I returned to Amazon.com to find info on the manufacturer and clicked on this link: Product Warranty: For warranty information about this product, please click here [PDF ]. This document said, "Any claims must be coursed directly to KORAMZI's Customer Service Support Hotline 213-744-1897." When I called that number, the representative said that Amazon.com did not understand that their company is not responsible for the warranty of this unit, which is sold by MRP Sales. However, he was willing to send me a new power cord to see if that would fix the problem. It did not. As much as I enjoyed the converter box while it was working (great for my Visio TV that has a failing tuner), it worked for a very short time and there appears to be no actual warranty. At least it (plus the extended warranty) came to just under $30, which I now write off as a relative inexpensive lesson learned regarding Koramzi and warranties purchased via Amazon.

Video is fine but it has a lot of control bugs. Switching channels too fast will cause it to insert duplicate channels into its station memory. Or it will show video of one channel while listing another. Moving from high channel to low channel causes the preview guide to list shows in backwards order - the shows that have just ended are listed instead of the ones coming up. The timezone will stay programmed for awhile but will randomly revert to pacific time. The audio and video get out of sync all the time. The "dash" for HD channel number doesn't work. It takes forever after typing in a channel number for the channel to change, so it's hard to navigate. You'll need a different remote because the buttons are terrible and range is short.

I think these are mostly correctable with a software update, but alas, there isn't one available.

Got this in January, stopped working in May. I scan for channels but nothing shows up. I've unplugged it. I've used several different antenna with it and still nothing. I've contacted their customer service who said that they would email directions in order to return it and get a new one, but I guess that email got lost in cyberspace. If anyone had a similar problem and knows what to do with this piece of junk, I'm open to suggestions.

So I have purchased this Koramzi after the Mediasonic Homeworx HDMI was giving me problem.
After having used both, I would say both units software menu looks almost identical, same remote works on both except for some button layout difference.
Initially the HDMI was giving me problem, the Koramzi splash screen show up once then the unit LCD just show ---- and no output on HDMI.
Then I connected to th RCA video source and was able to do the initial scan and setup, after that try connecting to HDMI again it works.

Like other have commented, the top of this unit is completed closed, so no heat ventilation and it does get hot.
The clock setting doesn't keep the value.
I tried 2 recording, issue is both program fro 2 different stations are recorded in same file it did not stop after the program time.
As for recording video quality, it is what every the station bit_rate send out, for example local HD station 5 minutes recording is 1GB in size
whereas the 5 hours from the recording SD station, that did not stop was only 5GB.

Wish there was a way to limit recording resolution/size because with current software in the box it is not practical to record HD stations for long duration.
Other than issue with clock not saving value and program recording not working properly, the quality of the HD recording is decent.
Overall not to happy with the quality of the programmed recording feature, but it was okay considering the low price.

I bought this for use with this antenna:
https://www.amazon.com/Mohu-MH-110585-Amplified-Lightweight-Detachable/dp/B00AVWKUXE
in conjunction with an old analog-input (RCA) TV in my workout room.

I am very pleased. I was not expecting a useful onscreen program guide. closed caption is nicely rendered as well, for when I do not want the noise if I am exercising in the early morning.

No digital radio in my area and I am not using the recording / PVR capability.