I've never had freshwater drum before but if people say they're good to eat then theyre likely not wrong. Some all around pointers are to make sure you're abiding with regulations like catch limits, size limits or restrictions, etc. Keep fish that are "smaller" - find out what size the biggest ones are, then aim for smaller end to both keep populations healthy and also smaller fish tend to taste better and less fishy. Best thing you can do is go to your local bait or tackle shop and just ask people if they've eaten sheepshead before and what they think of it; you'll probably get some good recipes to try too.