In this talk, I will share our recent work in developing a grey neutrino transport algorithm based on the M1 formalism for use in core-collapse supernovae (Andresen et al. 2024). We extensively compare with 1D and 2D simulations from various transport codes as well as our own energy-dependent M1 code. We see significant speed up compared to the energy dependent version (4-5 times faster) with only slight degradation in the neutrino signal and the dynamics. I'll also share some other recent work by the Stockholm group.