Right now I find PraziPro to be the best. It offers good economy and it works well.
I think the BIG key is realizing that in colder water, the life cycle of Flukes is longer. Also, there are egg-laying and livebearing species of Flukes.
So people treat once and think they’re done.But it might be a good idea to follow label instructions or treat several times 3 to 5 days apart. In a smaller, Community Tropicals biotope / tank it’s not that bad costwise.