The resin is pretty expensive and it requires cleanup after the print is finished(washing off excess resin) Parts cost more to make with resin and you cant utilize all the resin because it must cover the entire print, because of this they do not need to generate support material though(in some cases). However they can be very accurate. Extruder printers have cheaper material , and use it more efficiently. They can also print stronger materiels such as nylon or ABS not just PLA. But they need support material for some parts.
