My cheap Chinese soft close cabinet hinges have mostly failed. The brittle plastic insert in the failed hinges have grenaded, which lets the doors hang slightly ajar.
I spent some time getting educated on what I needed and ordered one to test for fit/function.
They are Grass brand, made in USA, 1/2" overlay, soft close, 45mm, screw on mount with 3 way adjustment. The selection fits as a direct placement, which means no drilling new screw pilot holes, so I ordered enough to replace them all now.
I found them at woodworkerexpress.com. $2.10 each.
Lots of other websites had the same or comparable hinges for LOTS more money. I have no interest in the company other than as a customer.  
They have a ton of all sorts of other products too.

45mm? Must be china.  My hidden hinge jig is 35mm so I use blum hinges.

They have a Blum that would have worked but it's 45mm also.
http://www.woodworkerexpress.com/Integrated-Soft-Close-Hinges-105degree-COMPACT-BLUMOTION-38N-Soft-Close-Hinges-For-5-16-to-3-4-Overlays-Overlay-1-2.html

45 mm seems to be the spacing on the mounting screws, correct?
Is the 35 mm the diameter of the mortise?

Could you post a link, or explain how you learned about the hinges? I wouldn't mind replacing my kitchen cabinet hinges with soft close. the previous homeowners remodeled the kitchen in Aug. 2014 and used off-the-shelf Home Depot cheapo cabinets.

I'm not even sure the door panels are heavy enough to close a soft close hinge. Does that matter? Does a soft close hinge pull itself shut once it hits the soft close point?

From my experience, yes, the soft-close pulls itself shut once it hits that point.

I googled "cabinet hinge glossary." I think Rockler.com was the first hit and had good info. I looked at another site also. I saw hinges described with different overlay sizes and googled cabinet hinge overlay and found info on measuring that also.
Yes. The hinge closes itself. The failed ones were a spring action and the new ones are like a hydraulic action. Not sure how they work, but when the door is about 5 inches from closed, the door will slowly draw itself shut if you let go of it.
I replaced the test hinge on a 16x34 door that had 2 failed hinges. It closes the door shut fine by itself, so when I get the next order and replace the other bad hinge, it should be even better.
FWIW I have framed cabinets with full overlay doors and fully concealed hinges (not visible when the door is closed.)