Since I got my RS130 a few months ago, I have been using it with FINISAR’s FTLF1318P3BTL SFP module since it is recommended by many users. And no doubt they work nicely together.
However, this doesn’t stop me from trying various SFP modules from a few different brands over the months.
At present, I am using HAUWEI’s SFP-GE-LX-SM1310 module in my system. To my ears, it sounds nicer in high-frequency portion; and the mid- and low-frequency ranges are comparative as good as the FINISAR.
Worth a try if you don’t give a damn to the nonsense that Hauwei stuffs could endanger your country’s national security. 
Do note to pick the module with the code starting with 0231… next to the logo. The salesman said that the numbers represent the module is a higher-spec model.
