Is my NOISE FLOOR (NF) really worse than yours ?

Well, let's answer that question first so you can move on to better things in life. And the answer is:

No it is not, because I use an S-Value indicator (S-Meter) that follows a Standard! The so called 6dB per S-Point (6dB/S) standard!

And that's it, 73 and catch you on the bands (as they say).

Oh, hello you are still here. So, it looks like you would like to know a bit more about this phenomena. Well, then read the below or maybe this .........

As far as I know, most Amateur Radios Transceivers from the three main manufactures, ICOM; YAESU and KENWOOD seem to have settled for a 3dB/S scale below S9 (-73dBm). 

So if I read a Noise Floor (NF) of S3 on my S-Meter, which by using the 6dB/S standard would be -109dBm or -2.0dBμV NF.  And my QSO partner, i.e. you, is stating a NF of S2 which, using the applied 3dB/S scale would be a NF of -94dBm or -13dBμV.  

So is my NOISE FLOOR really worse than yours?

Let's have a look at the below two Tables, the right one is scaled in 6dB per S-Value i.e. my S-Meter and the left in 3dB per S-Value like your S-Meter. 

Received Power (Zin = 50 Ω)	Signal Strength S-Value 6dB step		Received Power (Zin = 50 Ω)	Signal Strength S-Value 3dB step
-121 dBm	1		-97 dBm	1
-115 dBm	2		-94 dBm	2
-109 dBm	3		-91 dBm	3
-103 dBm	4		-88 dBm	4
-97 dBm	5		-85 dBm	5
-91 dBm	6		-82 dBm	6
-85 dBm	7		-79 dBm	7
-79 dBm	8		-76 dBm	8
-73 dBm	9		-73 dBm	9

Doesn't that shed some light on this (issue ?)

You might like to read this if you are not that concerned about S-Units and dBm's etc. but don't go around spruiking that all S-Meters are correct.

Or if you really want to know what your S-Meter is displaying you could read this. 

IARU Technical Recommendation R.1 Note: This is now being omitted from the latest IARU HF Handbook. You can find an excerpt here.

Signal Level Strength Meter Calibration and IARU Standards