I wouldn't call using a Sulfur Denitrator old school by any means. They work well, and are used by many people. They are just one way of many to lower nitrates.
Best advice I got about using one is determine if you even need one or not, meaning determine if you have elevated nitrates before setting one up. I don't know if you have done this or not, but testing every couple days for three-four weeks can get a baseline and help make that decision.
From my use of one, I would advise you clean it out every 4-6 months, as they can get clogged with dead bacteria sediment and make it hard to control the effluent rate. I also believe clogged denitrators can emit hydrogen sulfide.
Finally, a Zeovit system can give you a beautiful tank, but it is so much more than nitrate removal. It is a complete nutrient/bacteria management system, and requires about 1,000,000 times more work than setting up and maintaining a Sulfur Denitrator. The additives are expensive, and require a strict commitment to a schedule of dosing and reactor maintenance. I considered doing it once, but decided not to because of the highly regimented schedule you have to maintain.