HiFi Tuning Fuses: Impressions and a Question

I recently purchased a HiFi Tuning fuse for my Classe CP-700 preamp. My initial impression is that it is slighter darker sounding than the stock fuse. The sound is also a bit more liquid which is actually nice since the CP-700 can be a little lean. Vocals now have a weight to them. However, the clarity of the CP-700 has not been compromised. The HiFi fuse also seems to tame the highs a bit. My system was not bright to begin with but the HiFi seem to either roll off the highs or mask them a bit. I am not sure I feel about this. This characteristic combined with the darker, more liquid sound, makes music very smooth and easy to listen to me. It actually reminds of listening to Sonus Faber speakers, sweet, romantic, warm, easy, smooth. Is the HiFi Tuning fuse better than the stock ones? Like everything else in this hobby, it is not a matter of better or worse, it is a matter of a different sound.

I also have a question about fuses in general. My stock fuse is rated at 500ma at 250V. The HiFi Tuning fuse is rated at 500ma but at 500V. Remembering waaay back to my college days, V=IR, therefore the HiFi Tuning fuse has a higher resistance. So what does that mean? Does it matter that it is rated at a higher voltage than the stock ones? Will I harm my preamp using this fuse???