john_g A 5% difference in rating should not be a problem. Phone SR if you want confirmation. My amps are rated for 5 amp fuses but require 8 amp due to their enormous storage caps which have a huge inrush which popped the 5 amp fuses. (SR exchanged the blown fuses for the appropriate ones).
My amp designer friend who has NO tweaks in his system immediately heard the difference in my monoblock amps he designed using the blue SR fuse over the 5 amp Littlefuse (a new one too). He decided (he's cheap) to install 5 amp breakers to replace the fuses. His amps sound about as identical to mine as we can tell. Whatever it is, the cheap fuses are INFERIOR in our amps than SR fuses. The blue fuse sounded great immediately without the mandatory 72 hours the black fuse required to stabilize. I also use the blue fuse in my heavily modded Dynaco ST70 and that is a substantial improvement over other fuses.
My amp designer friend who has NO tweaks in his system immediately heard the difference in my monoblock amps he designed using the blue SR fuse over the 5 amp Littlefuse (a new one too). He decided (he's cheap) to install 5 amp breakers to replace the fuses. His amps sound about as identical to mine as we can tell. Whatever it is, the cheap fuses are INFERIOR in our amps than SR fuses. The blue fuse sounded great immediately without the mandatory 72 hours the black fuse required to stabilize. I also use the blue fuse in my heavily modded Dynaco ST70 and that is a substantial improvement over other fuses.