I know that the center in Richmond, NH has been regularized by, and is in good standing with, the Novus Ordo bishop. As far as I understand, the center in Still River, NY is not in good standing with the Conciliar sect.
This is incorrect.
There are two different facilities at Still River, NH: Saint Benedict's Abbey and Saint Benedict's Center. These are separate but both are legitimate spiritual descendents of communities founded by Fr. Feeney.
Both are now regularized and in canonical standing with the Church. St. Benedict's Abbey is a Benedictine abbey, as its name suggests.
Saint Benedict's Center is home to the male and female orders of the Slaves of the Immaculate Heart of Mary.
A third community, also named St. Benedict's Center, is sited in Richmond, NH, having separated from the Still River communities several years ago.
This Feeneyite body is also recognized as regularized and granted canonical staus by the Church (Diocese of Manchester).