Price is great! Picture is great! Audio needs help. Pass through HDMI loses Audio when commercials come on requiring you to either reboot the box or change the source HDMI stream to regain audio. On the receiver end, the audio drift (Lip Sync) is good for a few minutes but then drifts to the point it is unwatchable. If I change to another channel and change back, it is back in sync for a few minutes.

The unit is not Dolby so it does not sound on most of the US TV sets where the Dolby is mandatory. I had to find this myself as the tech support never respond at all. They do not know, probably is not made by them. There are no settings for the major minor channel so I could not make it to the position I wanted. Some resolutions on input are not working so I could not connect neither my direct tv nor my dvr in 1080i 60.
And it does reduce the quality to 720p as the box does not encode any full hd, so if you input 1080p, it scales it down and you receive half quality on the tv.
Apart these huge limits and the non working audio on most tvs as it is not Dolby ac3, a good basic device

I have been wanting to get an ATSC modulator since the digital transition in 2009. The problem is that they usually cost $800 or more. Finally this became available at the $300 price point, still more than I'd like to see ($100 would be more appropriate) but this one seems to fit the bill for my needs. I have a house with 4 TVs all connected to a roof antenna. I used a 2 to 1 splitter to combine the antenna with the RF output of this unit, which then feeds the input of a 8 port amplified splitter to which each TV is connected. Works great, changed it to channel 52 to get above the broadcast band (I have a 4G signal trap).
The unit works well with my Roku Stick (RF/app remote) allowing me to watch Netflix/Hulu/CBS on all TVs at the same time so we can watch shows while we do chores/get snacks/etc. It outputs 720p but takes 1080p or 720p in. A few things I noted...audio doesn't seem to work on my old 2009 Vizio, as if it doesn't have a codec for it or something. Also, HDMI volume seems very loud, still trying to figure that out. There is noticable lag when using the remote but you get used to it. Haven't tried USB yet. Must say that the picture is great on my 42" Samsung TV.
Not many frills but it does the job. Would like to see some more features maybe through a software update, which it does have a separate USB port for.

very nice interface with great quality images

This is a nice solid modulator built to "set it and forget it".
One option I don't recall in the specs is that it does have a USB jack for thumb drives probably fat32 formatted, to play mov (QuickTime) and avi files. This USB slot is the one on the side, not the one on the back.
It accepts up to 1080p60hz hdmi input/throughput but as the tvs I will be using are all going to be 720p I cannot tell if the throughput to the cable tv channel can be greater than 720p EDIT: I did go to the suppliers website, the only output to cable is 720p. The hdmi throughput to the local monitor should same as the input hdmi

I was able to power it up and immediately begin to send a signal out to channel DTV 14-4. Once I scanned the channels on the tv I had connected, the picture came right up. The audio from my pc came through fine, but until I figured out the settings on my tv, I was unable to view the entire computer screen. I say this because it was the tv settings, Not this hdmi to astc modulator box.
I am very satisfied with the way it works, The manufacturers could have printed the font of the instructions a little larger, but if you read them you will see they are very accurate. It does not have a remote, all interaction with it has to be done from the front panel. As I said, it is designed to be set and then forgotten about. It comes with some screws and a couple angle brackets for wall or cabinet mounting.

I will be using it in a church to send video from cameras and computers through a 4x2 hdmi matrix switcher out to several tvs that we are currently using with composite input. This will greatly clarify the picture seen in the cry room, pastors offices and rectory. Also it allows use of the cables I already have in place.
I will be able to remove an amplifier from service helping with electrical costs as well.

The only potential issue is that there is a 100ms delay between the input and output so any monitors which are in an area that someone could hear the live sound they would notice the difference.