I've got both a Google Cardboard as well as one of those plastic headsets. tl;dr they're not worth the money.
The cheaper plastic VR headsets are rubbish: a lot of them have worse lenses and a smaller field of view than even the cardboard Google Cardboard. They're designed more as "personal movie viewers" than VR headsets, where you're using your phone close up against your eyes to try and mimic the experience of having a big screen theatre.
The more expensive ones (might) have better field of view, and give you a more immersive experience when you look around (All heavily dependent on your phone screen size and resolution, of course). They're okay for playing around and getting a taste of (cellphone) VR, but the experience feels really unpolished and the amount of content is severely lacking. It's fun for a few hours, but the novelty wears off really fast. Unfortunately the whole Google Cardboard system seems very limited for several technical reasons.
IMHO I wouldn't spend any money on the Google Cardboard style plastic headsets. The new Daydream ones might be a different story but we'll have to wait and see. If you have a compatible Samsung phone, I'd consider jacksback's suggestion. The GearVR headset has motion sensors built in to deal with drift (which is incredibly annoying on Google Cardboard setups) and the lenses' optics and field of view are likely to be miles ahead of any of the cheap no name Chinese stuff. GearVR also seems to have a better selection of VR apps and games.
