The One-Electron SE iron is budget-ish iron that would be a good pick if you need to use global feedback.
These transformers are wound by Magnetic Components Inc. (Classictone) and are nicely made. This is likely also why One-Electron doesn't offer PP iron, as Classictone already does this. They also seem to be pretty well committed to paper bobbins and undoubtedly have decades winding these and practicing proper varnish impregnation techniques to avoid moisture ingress.
These transformers are wound by Magnetic Components Inc. (Classictone) and are nicely made. This is likely also why One-Electron doesn't offer PP iron, as Classictone already does this. They also seem to be pretty well committed to paper bobbins and undoubtedly have decades winding these and practicing proper varnish impregnation techniques to avoid moisture ingress.