Do any of you know/have FMS Grey Speaker Cables?

I got these over 13 years ago and they are the only thing left I have from my original system and that I'm still using. Does anyone know how they would compare to what is out there now? They have performed faithfully through all the changes but I don't know how good they are and if I'd get a big improvement if I replaced them.

They are grey in color and a an OFC copper stranded litz wire surrounding a teflon core.

Thanks for any info!
I believe that is the FMS Waveguide speaker cable.It is a competent performer.What areas would you like to improve ,above and beyond their performance?
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I have a bi-wire set. They're about 3/8" diameter, and a red & black wire emerge from the ends. Seems like they're twisted around a core inside the jacket. I'm not sure they're Litz though (but I haven't checked closely). These speaker wires weren't too expensive.

Let me know if you want to sell yours, I could use a matching set for my new Center channel!
I think Ladderlake has the original "FMS Grey", not the grey jacketed "WaveGuide" Kjweiss is describing. The design is similar, but not the same. The "202" version of WaveGuide is the best sonically. -AG
Thanks guys,

could you describe the what I have vs. what's out there now?

The FMS "Grey" SC is from the late 80's. It's very well made with "FMS" helical serve conductors in OFHC enamel coated wire with TPFE tape dialectric. The design was for AudioQuest but our relationship with AQ (1983-1987) ended before the cable was made. AudioStream (Paradigm Loudspeakers) licensed a version the design made with bare copper and sold it as Audiostream Black. Changing the construction from enamel coated to bare copper did not have any sonic penalty, which surprised me (and Bill Low). I kept working on the design with bare copper, and in the early 90's it was manufactured and sold as FMS WaveGuide, first "102" then "202". Many miles of this cable (2-15,000 ft runs and one 25,000 ft. run) have been sold. The "202" is the best of all of them. It is much more transparent (Harry Pearson definition) than the others. This gives it a 3D realism that goes beyond not only the previous versions, but most of what is currently available. I have been in demo rooms and heard 202 embarass $10K cables.
Thank you Fmscable for your descriptions and time...

Where can I find these current products?
Does anyone know what the price for this cable, say 8 feet bi wiring?