Which Mundorf for my tubes?

Don't you know the rule of "more expensive and harder to get" is always the right way to go if you are an "audiophile". Precious metals, diamonds, exotic ancient woods are always the thing to do. Especially if each of the caps is made in a very laborious way, by hand, and only by little Women with small hands.
The only exception are the true heavy metals on the periodic element chart. They can cause problems like Leukemia or at least a bad sunburn like area of your skin and sloughed off mucus membranes.
Except the Cobalt in Alnico speaker magnets it's particle emmisions are too diffuse to cause harm and is no more radioactive, than a regular sidewalk. No- sidewalks are not dangerous. Some Cobalt however is very dangerous, don't buy anything that says enriched except breakfast cereal.
Palladium, Platinum Irridium, Gold and Silver must be in the mix somewhere. And in truth Silver really is a superb conductor.

My personal preference is for the Silver Oil, but I have seen a folks who prefer the Silver Gold.

I don't think you will be making a mistake either way. Just be sure you have enough space, the Mundorf caps are a bit bigger than average (I use the term average loosely)

Another cap I like that is less expensive and a little smaller than the Mundorf is Dynamicap.

Regards
Paul

Would have to agree with Pauly. The Mundorfs are are very good caps, if not the best.
Have been replacing all my Auricaps with Mundorf Golds or Silver. The Mundorf Supreme is about comparable to the Auricaps. Have replaced all my Dynamicaps with Mundorfs also. They can be a little zippy in some cases.
Replaced the caps in my Modwright pre with Mundorfs and they walked all over the Vcaps they replaced.
The Mundorf Gold is a good step up from the Siver if the quality of the equiptment is high. As Pauly said before, some of the Mundorfs are large and some Golds are huge.
A good source is Soniccraft which will also give you the measurements to determine if they will fit.

Get a look to my previous tread .....