Well, not exactly. The reference GC provides quite a bit more detail. It does appear to close down the sound stage width for some systems The net effect being much more information retained, in those areas covered by note and transient specific internal gradient information, and more wide band low amplitude coherence in general.
The standard GC provides the same sort of information retention, but it is not really close to the reference units in retaining as much of the specifics pointed to above. They don't either of them have any sound character at all. Whatever level of resolution your system is currently capable of, these two will help retain the back half of the wave form of that level.
Having said that, most modern day systems have a tremendous amount of information, in the signal side of the electronics. It is the lack of care for the audible properties of grounds that GC is rectifying.
I realize it is hard to grasp how the back half of a wave form might be important. We aren't adding anything to the characteristics you are already familiar with. We are just making what you have far more complete than it is without some form of attention, to the audible portions of a proper ground system.
As for the RCA units, in my tube preamp which is off having some radio frequency oscillations squelched, the reference RCA all by itself was exactly what was needed to free up the sound from a slightly slow, very sweet and clear character. All that occurred was a sense of agility, quite a bit better rendition of instruments within their performance space and greater wholeness to the entire sound. Everything sounded complete, in comparison to no reference RCA. The standard RCA had an effect similar in character, but not in degree of information completeness, and the resulting depth of field illusion. In that case, there was no narrowing of the sound field, with either of the two.
My recommendation is to go slow. If you have a CD player, or outboard DAC with an available input or output, that is contiguous between channels, try the standard RCA there first. If you like the change, try another on your preamp, again with the same stipulations about contiguous grounds.
Before you do either of these I would suggest a pair of the standard GC lugs on your speakers. If you decide to move to the reference units, these standard lugged units can go on the other end of your speaker cable. I don't think you will find you need more than this. However, once in place the changes wrought by the RCA units will be much more effective and available.
Almost all modern audio gear has contiguous grounds, with only some outboard Dac's (Peter Daniels comes to mind) having proper ground planes, with separate channels and power ground separate from signal ground.
Since there is a money back guarantee on these things, I am sure you will know if you are satisfied within the 30 days allowed.
Bud