After much research I chose to upgrade my 45 year old furnace and eight year old heat pump with Lennox end of December 2006 costing $6200 installed. The xp-15 heat pump had a system operations monitor, which sounded like a plus. Musts were energy efficient, quiet, and new refrigerant (which wasn't required yet. But I wanted, at additional cost of $500). With new system, winter and summer bills dropped $50-$100 month. The heat pump unit at 63Db is very quiet; inside house with new Lennox Elite furnace, unless you see something by vents moving, wouldn't know it was on; everyone comments on it. Now for the bad – for the first three years, every season change there were problems; adding up invoice costs for that time totaled about $700 for replacement of txv valve, coil, defrost sensor, defrost sensor coil. Apparently the sys. Ops. Monitor wasn't very helpful, lol. Finally repairing a crossed wire in H.P. (so tech said) fixed it. Viola, that was the last of seasonal repairs. After 2 1/2 yrs. Of quiet, efficient heat and a/c, Feb. 2015 was 1st repair needed at $479 to replace defrost board in H.P. I've paid for a maintenance pkg. Yearly with a great local HVAC company, giving me priority service (a must!) calls, reduced rates and a furnace and heat pump tune up. The H.P. is 10 years old now, I'm hoping it is as good as my next door neighbor's, her Lennox is 17 years old and works great. I'd be hesitant to buy a Lennox H.P. again because, based on reviews, sounds like blades are plastic and ice up – we get cold in Ohio. I'd look at Trane, as neighbors and friends have had very good luck with their units, and they are reasonably priced.