Why would you ask if a cable would improve your system? Nobody has your system, or your room, so how can somebody know how your system will sound with a different cable? Only you can tell if a cable will make your system sound better.
Also, what’s expensive? $50? $500? $5000? I have never heard a $50 or $500 cable that made my system sound its best. The cables that made my system sound its best cost way more than $500 each. But if you do this auditioning of cables, you want to make sure you are keeping your equipment because the cable you buy today with your current gear might not be the best cable for your new gear.
Get the gear you want for the next few years, then audition cables once you break in your new equipment.