Ignatians not only offer the Holy Sacrifice of the Mass according to the classic Roman liturgy (termed the „Extraordinary Form of the Roman Liturgy“ in Summorum Pontificum by Pope Benedict XVI) but also place it and the rest of the traditional liturgy at the source of their asceto-mystical determination, i.e. spirituality.
For those not familiar with the classic Roman liturgy, the following is a link to a filmed traditional Latin Mass with explanations by Archbishop Fulton Sheen:
Also, a video of the Mass of the Ages as enacted at the English seminary, Ushaw College in 1960: