I've been following this thread for some time, most informative on web. Thought I would relate some of my experiences with fuses. Most have been positive, use SR Reds in some of my equipment. However, I've had problems with blown SR fuses in two of my 845 SET amps. My Art Audio Carissa Signature twice blew SR fuses on initial start up. Recently, my Coincident Turbo 845 SE blew 4 SR fuses in succession (I don't recall any generic 6.3a fuse failures). Two 6.3a slow blow (stock value) and two 8a slow blow all blew up on initial start ups. Three were replaced free of charge after communication with Synergistic and dealer, I could not get reimbursed for the last 8a, SR wanted me to replace with 10a which I declined (now aprox. 40% above stock value) and dealer simply ignored me. I notice some dealers are now stating on their web sites no warranty/no returns on audiophile fuses. Probably getting burned too often. My take: Be wary if using these in high current amplifiers.
These failures also cause me to speculate as to SR versus generic fuse protective capabilities. It appears that SR fuses are overly protective, I just wonder about protection in steady state operation (after initial start up inrush current). If a generic 6.3a fuse can withstand repeated inrush currents and even 8a SR fuse can't withstand a single inrush current how can they be protecting the same in steady state operation. Perhaps a 10a SR fuse would have an approximate equal protective capacity to 6.3a generic fuse in steady state operation? It seems logical that inrush current overages and steady state overages would hold steady, thus, the fuse should survive and or fail accordingly. All 6.3a fuses should be able to withstand exactly the same inrush and steady state overages. I would think there has to be an exact breaking point for the wire in the fuse and this would be the same for all equal value fuses. Obviously, there is not this degree of standardization and/or exactitude for fuse manufacturers. Makes me wonder about the exactitude of equipment fuse ratings.