I've schedule a few recordings & played them back just fine... the quality was as good as it was live through the OTA antenna. The fast forward & rewind worked decently, but not as good as a Cox/DTV DVR. You can pause live TV, but there are limitations... if you're watching something live then you have put it into "Timeshift mode" (by pressing pause) in order to be able to be able to pause/rewind so it isn't automatically recording everything you watch live like better DVRs do. I'd also recommend increasing the amount of TimeShift hard drive space to 4GB (default is 1GB) so that you can leave the TV paused longer if you plan to use that feature often. I haven't tested it enough to tell you exactly how long you can leave it paused.
Overall, the menus (& remote) are clunky/confusing, but once you figure it out then it works pretty well. They have a channel guide that you can go about 24-48 hours ahead to schedule a recording or you can manually set up a date & time range to record a particular channel. It only records one thing at a time & it has a 2TB max limit on the external hard drive (a 1 hour recording was about 6GB) & I think USB 2.0 was recommended. There's also an option to always record a certain show/channel in a specified time slot every week, but I haven't tested it yet. Plugging a HD larger than 2TB can cause the thing to crash from the reviews I read. Recordings are in .mts format so you can actually plug the hard drive into your PC & play them with the VLC media player.
I just got it last week so that I can record the 2nd pre-season game while I'm out of town. There's also a way to hook it up to the Xbox One like the Xbox TV Tuner so you get the Xbox guide, but you still have to use the clunky DVR menus & remote to schedule recordings. There are much better DVRs out there, but I don't plan on using this for much more than Cards games & maybe some CBS shows that don't stream through Hulu.
EDIT: One more important thing, you have to leave the DVR "On" for it to record things... if you put it into standby mode then it does nothing.