Either my eyes are getting bad or the lighting in my house is poor...I am hoping for the later. My question is this: What is the size of a Rubik's Cube brand cubie (side length). I am geting 11/16 of an inch..is this correct or is it closer to a metric number?

The number I've always heard is 19mm per cubie or 57mm for the whole cube.

Oh, that's so quaint, 11/16" Reminds me of this cartoon. BTW, you should be getting closer to 3/4" (actually 187/250" ) for the cubie size for a "proper" 3x3x3.

Gus, that's still common across the pond.

Of course, but that doesn't make it any less quaint

While we're on the subject.

What is the amount space on each 5x5x5 of where the sticker lays for the Rubiks/Mefferts and Eastsheen and V-cubes?

According to Cubesmith's page it's .413 inches or 10.5mm

All Rubik's brand cubes (from 1980-2012) are 57mm total, 19mm per cubie. Many of the newer speed-cubes in Asian markets for whatever reason are 54mm, 18mm per cubie. Maybe Aisians have smaller hands than Americans? I have large hands but don't even notice the 3mm difference. And I believe the standard Rubik's 4x4x4 are 16mm per cubie, or 64mm total.

Rubik's thick, sturdy plastic and mostly square internals, while being somewhat mediocre in terms of general turning quality, makes up for it as they are still the best cubes around for construction mods. The old Rubik's 4x4x4 and 5x5x5 (before they started using rails) also used to be really good for modding.