We bought the Harmon Exception last summer - it heats the approx 1700 sq ft main floor, plenty warm in the living, dining, kitchen, and laundry rooms, keeps the 3 bedrooms at the end of the hall between 63-65 degrees. There was a learning curve (unless you like a lot of heat), but we haven't run the 3 main floor furnace zones at all this year. The top load feature, the non-catalytic re-burn system, and the HUGE ash bucket are the greatest features.
Unless your main room is huge, the TL300 seems like overkill. Nice looking stove though. Which ever one you get, you'll like the Harmon brand.
Steve