I used to use Seimens which I liked a lot, natch, but one went bad so I tried JJ E34Ls which sound great for cleans, maybe even better than the Seimens, but a bit edgy for dirt. I just tried Svetlanas which sound really good in my '74 Super Lead but the cleans with the PT100 are lifeless compared to the E34Ls. Dirt is good though with a smoothness and rich mids. What do you guys like? I don't want to throw down for NOS right now so I'm looking at new production.