Disclaimer: I know nothing about specific curricula for math.
Singapore math is the one I saw railed against in an article this morning (by a fed up teacher who quit). Ironic.
Funny- Singapore Math is the end-all-be-all here, and is only available in one of my neighborhood schools (the richest one that pretends it is a private school and has a waitlist a mile long). When I went on a tour of their school its all the principal would talk about.
But also, evil!
All math is evil.
It may not have been the program itself as much as the switch to the program that the teacher took issue with. They had a curriculum that worked well and teachers were trained on, and they changed to Singapore making teachers have to do more timing. Her problem was the amount of assessments and teacher training and data collecting takes teachers away from the classroom making it hard to meet the kids' needs. I'm sure she's right.