I've over 500 hrs on them.
I thought I had seen some Platinums in the picture. Those guys do not come into their own until about 550 hours, but it sounds like you are there
Did you consider the Flat stack HT?
Those dudes are about extinct
However, we still have some stock, and they are on Sale
I am there with you on considering going to copper foils. My Exotica 3s use 4 15ufs and two 30ufs. Pretty awful cost wise.
Do you have a schematic? If not, could you draw one? There may be options. In any event, I'm sure we could help you out
They'er the copper foil, I thought about the flat stacks but decided the speakers were worth the extra expense and I feel the results were worth it.
Price to performance ratio... This is where Sonic Craft strives to bring it. Not all parts performance can be judged by their price, but we try to stock "only" the parts that perform up there with their price. We want to hit everyone's budget, but not at the expense of value. If you move up, I want you to enjoy an improvement worth the extra coin.