I compared SFP+ Finisar FTLX1475D3BTL to a DAC cable tonight for 30 minutes (I have about one month playing time with DAC cable), I like SFP+ Finisar FTLX1475D3BTL better than my DAC cable based on my system.
@Yu3319 The SFP+ Finisar FTLX1475D3BTL uses 2 core fibre, doesn’t it ?
I am tempting to try it since the SFP I am using from RSA720 uses single core fiber. Curious to find out if two is better than one. 
Yes, use two core Corning cable single mode cable
Thanks. I’ll definitely give it a try later.
Please make sure to use Corning cable as is better than other cables that I tried
Noted. May I know where you got the cable and do you have the parts number for it ?
Also, does the Corning cable in blue or yellow color ?
I believe that single mode is always in yellow.
I forgot where I purchased the cable. I need to check it
Thank you. I searched a number of cables but I am not sure which one is the correct one. 
Just ordered a pair of the Finisar FTLX1475D3BTL. And will order the cable as well.
Thank you very much !