PS - We almost bought a 983. A Coalbrookdale Darby stove came up and we bought it instead. Not surprisingly, very similar in specs to the 983.
We would have gotten the 503 for no-compromise, simple, coal heat but came upon a coal/wood boiler that will be the 'central' system. So we headed for a 'compromise' stove, in order to burn wood on cool nights.
(I don't like compromise solutions if they can be avoided. What threw me was beauty of the cast iron Darby, so this really wasn't a rational decision.)
If your purpose is to heat your home in a simple, no fuss way, I'd go with straight coal and the 503. If your fireplace is for the 'weekend fire', with (massive) backup heating capability, then the 983 is a good choice.
Great value in the Hitzer line, too.
BTB: a friend dropped off about 30 or so old apple and cherry trunks. I have about 5 cords of fruit wood to buck/split and burn, so I'm glad for the ability to burn wood. I enjoy the work, now, anyway.
But!... 2 full weekends of bucking, splitting and stacking (seasoning stack, not final) is not free fuel! I'm glad not to need to do this to heat my home. It's a *ridiculous* amount a work to prep the fuel, then feed the fire every 4-6 hrs! Hooey!
If you remember the Steve McQueen movie, "Sand Pebbles", I'm going to look like one of the ship's stokers down there in the basement.
"Honey, come out of the basement."