To address the OP,
In the U.S., at least, different bishops view Protestant baptism differently. Some will accept any trinitarian baptism by water. Others a bit choosier, accepting more sacramental-leaning Protestants (Anglicans, Methodists, sometimes even conservative Presbyterians) but not the radical reformers (such as Baptists, Pentecostals...who actually come out of Methodism..., Mennonite, etc.) Others still simply don't accept Protestant baptism at all.
I think all have valid points, and there's really not been a Church council to address the reception of Protestants (like other councils defined how to accept Arians, Nestorians, Non-Chalcedonians, Novationists, Donatists, Sabellians, etc.). Until that happens, I think you'll see varying opinions on how we should receive Protestants into the Church.