I’m good with it. I’m wondering if it just took a long time to get a bubble out or something. I still don’t think it puts out quite as much as the factory one. With my instant read kitchen thermometer I get about 140 degrees out of the vents with the blower on 1. 135 on 2. But only about 120 on 3 and 4. More airflow less temp. The cabin is plenty warm, but the defrost can’t really keep up in severe conditions.
I truly believe the heater core would outlast the rest of the car though. It is a quality made part. The company is licensed to make one off reproduction airplane parts.