Mundorf Supreme Vs. Supreme SIO and SGO?

I’ve tried all three. It’s very similar to going up the chain with tubes. The Supreme is a significant jump in terms of dynamics and boldness over cheaper capacitors. On its own, it is already one of the best, though I do also like Auricap XO, Jupiter, V-Cap and Miflex. That said, the Supreme can be a bit harsh on the highs and tonally imbalanced on the mids (emphasis on the frequency extremes). When you upgrade to the SIO and then the SGO, the sonics become more increasingly natural and balanced in a more effortless way. The SGO is completely resolving without fatigue, and more balanced than the competing bloomier film caps like Jupiter or Miflex.

They take the cake as my favorite caps to replace if the unit can fit them. that said, the SIO and SGO in respect are much larger caps than the Supreme, so ensure there is enough room in the chassis. 
 

Is this the same as the so-called GAD gold and silver foil capacitors made by Mundorf, a pair of which is in the Musetec MH-DA005 DAC?

The designer of the DAC writes, "In the analog circuit, there are two particularly important capacitors. We compared a variety of expensive capacitors, such as copper foil, silver foil, gold and silver foil, oil immersion capacitor, and finally selected the GAD gold and silver foil capacitor."

It depends on what you are installing the caps in to as to what is the better cap version to use, as tbd. I landed on oilers in my source and non-oilers in my amplification.  I'll likely replace the copper-oil caps in my preamp with non-oiler Mundorfs too.  Here is the latest:   

Tube Amps: now running Mundorf Capacitor Supreme EVO SilverGold Black SESG (non oil version) in my Mono Tube amps. Compared notes with an amp designer.    

DAC: now running Mundorf  EVO Silver/Gold/Oil caps (with oil).  Tried both oil and non-oil versions and prefer the oilers here. 

Spending up on really good Mundorfs paid off for me, and your results may vary.  

I've tried all 3, Supreme, SIO and SGO. I'd personally stay away from SIO, impressive at first as it's detailed, but not natural sounding. SGO definitely sounds more balanced. Supreme is the sweet spot for me, not as resolving but thicker sounding. I've had success using both Supreme and SGO in my previous tube amp. SGO in preamp and Supreme for the power.   

Duelund capacitors are highly regarded, see link that gives a comprehensive review of most audio capacitors available.