Got my hands on a PT800/PS1400 stack and looking at the networks all the capacitors are Elytone branded electrolytics.

The tinkerer in me wants to upgrade them all to modern film caps as they are close to 15 years old now. Since every capacitor is a NPE did Greg Timbers/JBL voice the networks with their ESR in mind? Or do the Elytone NPE's have a low enough ESR swapping them for a film cap wouldn't be an issue ESR-wise.