No problem -- especially at monoprice prices. Had I ordered what the sales guy said I needed I'd be really upset with you.
This kind of thing is often over-thought and also given very little thought and in both cases, the results can work. I have seen people solder RCA plugs onto Cat5e and call it a day, I have seen people use all kinds of coax for video, Belden shielded twisted pair audio cable, big buck stuff and often, the most basic way worked best. I like the baluns because the two ends are isolated, so I don't have to chase ground loops and I don't want to waste time doing that. I have also used small distribution amps when I worked for an audio contractor and we were doing mostly LDS facilities- some of those runs were close to 1000' and we used West Penn shielded twisted pair (Belden owns West Penn, now) and the amplifiers converted the signal from high impedance unbalanced to low impedance balanced, so we didn't lose fidelity or have noise issues. For 50', it's kind of at the limit I would use for high impedance without gain or converting to LowZ/balanced.
In most houses, this won't pick up much/any noise as long as the cable isn't run parallel to power wiring. If you must cross electrical wiring, do it at a right angle and maintain at least 12" of distance.
