The fuse rating is 6.3 amps 250 volts Fast blow.
I have installed in both my 100 and 200 the Synergistic Black fuse and it does increase my musical enjoyment, also tried the Fuurtech Blue and not as good as the SR.
Most importantly in my system, it generates the most enjoyable musical presentation when only a single device is only plugged into the 200 or 100.
Multiple devices at the same time appears to introduce some harshness.
Eventually my 100 will be replaced with a second 200.
My ears are the only measuring tools that I have.
The 200 runs around 85 F and 100 around 87 F.
My next move is to have the HDplex supported on Nordost Kones this will help air flow also.
Another thing is that the HDplex 200 is ruthlessly revealing with zero forgiveness and requires better DC cables than the supplied stock cables.
One of the things that experienced was an increase of sibilance - Ssssss out of vocals. Managed to tame with use of ferrite cores. This is not a 100% cure, a bit still exist on a few tracks but does not interfere with my listening pleasure that I take so seriously and sure you do also.