Well I suggest to all here, don't just rely on one pair of supercaps! Fact is there are many other necessary upgrades to get full potential out of a Duelund or Clarity MR. If you have not pulled out all the generic orange drop stock caps and other peripheries, including sometimes wire, and other Electrolytics in the power supply etc... You will only get a small percentage of sound enhancement.
I just for example went thru and removed all 80 parts in my phono amp, dumped in far higher quality film, and electro caps, along with some silver mica's etc... THEN the final touch was running a pair of Duelund caps on the main outputs with NOS tubes directly hard wired up.
I also did a friends Tube preamp, 100% tube, with 100% built in tube phono stage. The whole thing got large Jantzen superior coupling caps, with a pair of Clarity MR's on the outputs and no bypass caps. Nothing comes close, its amazing, and it had all Mundorfs with Cardas gold caps before that and sounded generic in comparison! There are quite a few high grade resistors, like Bradley's or similar, with solid silver wire.
So lesson is, there is no quick fix without doing it all right. Op amps, or tubes design, sometimes many resistors, caps, power supply mod's, you name it, it all adds up. So as a warning one pair of exotic output caps hooked up to a Chinese special circuit board with 50 other small caps on it that in total cost about 1.75 U.S. will not necessarily net you the best results.
As for the Alexander problem above, that is strange, but as I explained earlier in this thread I now tend to stay far away from any oil based caps inside electronic gear, save those for speakers.