I use CCI CBs to shoot out of my bathroom window sometimes. They are quiet enough to not require hearing protection.
I have had trouble with the Aguila rimfire ammunition as it gets older though. I had a brick that I shot up over a two year span and towards the end of the second year it was becoming unreliable. I stored it in the locker right next to the CI and Federal ammo which was quite a lot older but worked fine. The S/V Aguila shot good when it was new, but as it got older I began to have misfires and some hangfires which would sit for sometimes 20-30 seconds before going off. At that point I gave up and chucked the last couple boxes.
