By "Warming potential" I guess you mean "contributes more towards global warming," not "I feel warmer with natgas heat"? I had a heat pump in an apartment many

By "Warming potential" I guess you mean "contributes more towards global warming," not "I feel warmer with natgas heat"? I had a heat pump in an apartment many years ago, and the big down-side to me at the time was that it felt like it was always blowing cold air on me in the winter. I definitely valued the warm feeling I got from natural gas heat! But I suspect that heat pump design has improved a lot in the last 30 years, so I'd be willing to give it another try.