I guess this is a similar thing to changing the pot in a
wah pedal. Some people swear by getting the $20 ones while the majority of people couldn't tell the difference between a $20 one and a $0.50 one.
If the two pots you have are made from the same component types then they should be pretty similar. Perhaps there are discrepancies between pots regardless of their rated values ? dunno.
Perhaps you could try a switch cleaner on the old one ?, I've found it pretty hard to kill a volume pot or even a wah pot. If either get scratchy you can bring it back to life with a squirt of switch cleaner, and if it's really bad you can often pull em apart and clean out the gunk in there with a cotton bud.
Tony