If you can try it and take it back, go for it. I don't see any problem. There will just be an extra wire and connection there, that won't be used. Going with a longer cable may cause a little volume loss, or high frequency loss, depending on the design on the cable. One other problem since it is for a microphone would be some noise, or interference that the wire can pick up if it is not shielded. I don't think buying one or the other (stereo vs. mono) will change this. They both come in shielded or unshielded types.