It's probably not 4k per-eye. I would guess that for the price though, it's a no-brainer. It may be worth the 20 bux just for the wireless controller packaged with it. Someone took a short video through the lens, and the image looked surprisingly good. He felt it was worth more than the $50 he paid for it. The limited info I have seen on it makes it seem decent, but being only 3DOF there are only a few things it's good for:
Seated experiences with a game controller. There are some, but it's usually not the focus of VR developers.
Cockpit-type games like racing, flight sims, Elite Dangerous!
VR Videos (you know the type)
You'll get only 60hz refresh and no room-scale. You'll also see IMU drift, due to it having no external sensors to track the actual headset position. It's not a deal breaker, but you will need to re-center occasionally. Also, these things, like other PC-based headsets, will require a beefy system to drive them. Do you have a graphics card and PC capable of it (or plan on getting one soon?) If not, then save your money. But if you do, you should have ordered one before they change their mind. I just bought a couple just to play with
On a side note, don't use CD autorun and run the drivers through every virus, adware, malware and trojan checker you can find before you install them. I always find Chinese hardware a bit fishy when only CD-based drivers from executable launchers are used, which seems to be the case here.