Capacitor

The Duelund tinned copper is excellent ,slightly better then the Jupiter copper foil but only in a few areas not all ,a bit more top end resolution , the Odam I removed for the Jupiter in preamp section more realism and 
depth of instrument and tone in my system ,if you are using vacuum tubes 
then you may like the vh Odam cap. There is no Best capacitor 
For  every situation from many builds especially with speakers and many DIY guys I know .
the Duelund being Waay to big for many situations, and waay 
over priced for a small % improvement vs the Jupiter copper foil IMO.
the vh audio CU Teflon copper has the best resolution of any capacitor out there ,but very $$ but good to use as a bypass cap.

Reducing the value not a good idea ,when engineered the UF needs to be the same in s amp,preamp, in a loudspeaker 
maximum different change under3%
bypass caps for small  values very common to use .01 uf 
the vh audio Cu Copper Teflon are excellent as PauL mentioned
the VH CU is superior to the Odam  and can be used values .01 
are typically used in the HF range,but can put on a midrange also.

There are a bunch of very good caps ,I have over 20 years between electronics ,and Loudspeakers , I have  Vh Odams in a dac. And in a speaker ,very good capacitors . Millflex copper paper poly oil caps very respectable .
but, I find Jupiter copper foil caps outstanding in image depth tone and Bass not perfect but very good on top , the best bypass capacitors higher then 100 volts 
Are without question the VH audio CU -Copper Teflon caps which are VH Audio best capacitors .I mixed roughly 2+% ,to the Jupiter
copper foil coupling caps in the preamplifier ,A great combination now it is open airy and have excellent precision as well as very natural musicality .
personally I like better then  any capacitor out there including Duelund .
everyone has a opinion but unless you have tried this combination ,you are missing a special combination.

I have been doing capacitor upgrades for some time now i,especially coupling capacitors in dacs, preamplifiers 
and loudspeakers . The best capacitor for detail  is without question the VH audio CUTF  -Copper foil Teflon it only goes up to 
2 uf I believe , as a main Cap ,my best combination is
for main cap Jupiter Waxed paper Copper foil ,which inside a amp is good to at least 160+ degrees ,no more bees wax. Use  up to 3% of the VH audio CUTF bypass capacitors , they are pretty expensive and room in m any cases is an issue ,I just installed this in my Coda CSIB integrated , and helped a friend in his Loudspeaker this is better then the Duelund cast  capacitors 
at much lower cost they do need a solid 400 hours to fully open up 
But a fantastic combination ,and my preamplifier now is in another league sounding . If you email me I can send you a couple pics to show scale,size.

What I forgot to mention the Duelund are a great capacitors way too  much $$
and huge, they  are top notch caps great detail and depth ,just slightly better the the Jupiter in layering ,but the Jupiter Copper foil has great overall balance, and much less $$ ,they are within a % point or two of each other 
detail on top is very good on both  ,but the VH Audio CUTF  is the best of the best in that 
dept by adding between 2-3% in the VH as a bypass cap the best of both worlds
if you have  a capacitor you need 2 uf or under the VH audio are pretty neutral 
slightly to the warm side but very big and for a pr of 1 uf for example around $1k.
greatness  cost $$.