This month for sure!
For the few of you who own PMG SACD, here is an interesting fact on audiophile fuses I have tried (3). If you also own PMG 512, you just need one audiophile fuse, not two. I have one AM M2 fuse in PMG 512, and it improved the SQ quite a bit. The system sounded more involving with a bit more warmth.
So, I thought PMG SACD may get the same benefit from fuses too. Well, both Gustard and SR Purple fuses made the SQ worse; in fact terrible. Yesterday I put in a M2 fuse in it so both PMGs have them. The SQ was fine but I did not hear much improvement. The system has turned on for a couple of hours, and I just did not hear anything exciting.
So, I put back the stock fuse. This change has brought back the best SQ as I remembered. Turns out M2 in PMG SACD has made the sound a little softer. The background seems less clear too.
Here you go, one M2 fuse in PMG512 is enough, two are too many; at least in my system.
I have the previous PST and have an M1 in there and I find an improvement, not a drastic one, but an improvement–sounds better to me than the stock fuse. I think these things are system dependent. My DSD Mk 2 DAC has a Swiss Digital Fuse Box and Graphene Sluggo feeding it.
I agree, with PST I heard a small improvement from M1 and Purple, and more from M2.
SDFB and Graphene Sluggo prices have gone up a lot, but what stopped me using it was the additional power cord needed. I was highly disappointed that I heard a major difference from different power cords. 
That would be a huge rabbit hole that I did not want to dig in.
Agreed. This is why, for me, I limit my SDFB use to only one location - between the wall and the P20. I’ve already been through 4 different power cord combinations. Sheesh!
Well, I use the same power cord before and after the Swiss Digital Fuse Box, as I had a few in the other system and have had some great help getting a few more from forum members, one here and one on the Decware forum. And bought a few more to use in the system I robbed them from. I agree, using differing power cords on either side of the Box definitely influences the overall sound. I prefer the sound of the Box with the Graphene Sluggo to any of the fuses I’ve used, by a larger margin than any fuse to fuse comparison.
I only used SDFB on PSA P15 before, and it was indeed better than any audiophile fuse. But I was using a $5k power cord.
After a number of really great component upgrades, I found fuses made less improvement. On MU2 I am not sure if there is any meaningful SQ difference at all, and stock fuse sounded the best in PMG SACD for me. So, I am done in this area. 
I’m done in this area as well, with SDFBs on the SEW300B amp, the DSD Mk 2, and the ZROCK3, an M1 in the PST and stock fuses in the Verafi components (LNBH and SnubStation Zero). Great sound and no more money for changes.
Did you break in the M2 fuse in the PMG SACD? It needs +125 hrs. That’s the manufacturer’s recommendation and my experience.
That M2 fuse was taken out from MU2 so it had plenty of time. I put a new Pink fuse (it needs a fast blew so I ordered the correct one) in MU2 and it has about 30 hours, but I think it is a better match with MU2 so far.
Sometimes, when I played a SACD then realized streaming still has a long way to go to be equal. Often it is from playing one of the SACDs from Venus, and that is why I have more than a hundred from Venus alone. One example:
The bass alone beats any streaming SQ I have heard, even from DSD256 files in MU2.
I got my new toy earlier today, and I replaced Fidelium with FRR XLR at PMG512 a few hours ago. It did take a couple of hours to settle in (it is used) and I felt the improvement was there, but less than that of Grimm MU2. FRR at MU2 was an eye opener on how a great cable can offer improvement on SQ.
Then, my wife came out of kitchen and said. Wow, the clarity is much better. Well, I guess she has better judgement than me since she seldom commented on most of my other so called audio “improvements”.