“Also, quoting the Shulchan Aruch haRav to defend Chabad is like painting a target around an arrow. I don’t know of anyone other than Chabadniks that actually uses it to pasken halachos.”
It’s a respected sefer halachah in all circles. The Mishnah Berurah, Kitzur, and Piskei Teshuvos all use it. I’m not signing on to defend whatever you were arguing against wholesale, but this particular statement was just untrue.