I have a Central 6048, rated at 500,000 BTU (no clue how they come up wit ha rating, too many variables)
I highly recommend one. I use mine to heat the house, hot water, 32x48x12 shop, and pool in the summer. It is an excuse to play with hotrod saws, have a dumptruck, and an iron mule.
My situation is a little unique though. My shop where I work is here at home, and a good friend has a tree service. He calls, I haul. If I had a real job, and had to buy wood with actual cash, things may be different.