Jeremy it is a whole different cap I believe period... your run of the mill Auricaps, Solens, Kimber, mundorf supreme costing 5 dollars to 30 dollars in popular sizes are not a huge step from each other at all.. You want something special, in all Honesty you gotta pay the piper to go into the minimal 35 plus per cap small value stuff.. If your gonna do it and your only going after a tweeter your payoff will be in the end a special sound with the silver oil vs. another Good but not special poly plastic whatever cap.. By the way I have Silver Oils on just about everything in my system now, its the lowest end cap I trust to get the sound I like, and no its not low end but you get my point.. It seems to take them in speakers about 5 mins to sound not tight and compressed though, so when you first hear it on your tweets it will glare a little more than likely.. It will stabilize and Sibilance in like Womens voice and stuff will dissapear in probably a solid 20 to 25 hours... And daily they get better as they play. Same is true when I used them with my Tubes..
If you have a nice speaker and a 15 dollar cap vs. a 45 dollar cap is the only thing holding you up you gotta just go for it.. If a cap for 35 vs. 400 each is the problem then I understand.
Also somewhere on one of these threads or maybe on this one above there is supposedly a method to run High voltage thru the cap to burn that sucker before you even install and it will sound nearly perfect out of the box, maybe not voltage or whatever but something, I have no clue so don't take my word or dangerous suggestion on this.. I never did this and it could take 200 plus for them to show the most open and powerful sound.. Oil and Silver on tweets just sounds right. smooth and warmth, with a bit of magic.