What is the benefit of Sufi orders?

In general, Sufi orders are like schools for moral education and upbringing. If their method agrees with the principles of the religion, and those of religious law, then this is valid. If it does not, then it is illegal; and it becomes obligatory to correct the Sufi order with wise counseling and forbearance.
Ibn Taymiyya once explained that, among the Sufis are Imams of knowledge and religion. “In Ihya’ ‘Ulum al-Din by al-Ghazali, we find the words of the most knowledgeable and correct of these Sufis regarding the works of the heart; words that agree with the Holy Qur’an and the Sunna [of the Prophet], and the religious acts of worship and moral customs that also agree with the Book and the Sunna”.

He also said: “And those famous Sufis of the Umma who were true to the
Umma did not approve of such things [bad behavior], but they prohibit it”.

Ibn Taymiyya also gave permission to donate money (place waqf funds on) to Sufi orders, except for those who hoard money, or are bereft of ethics and do not follow Islamic law in matters or morals but rather are dominated by base desires and corruption; such do not deserve any reward.
He [Ibn Taymiyya] also described those of the Sufis who are counted from amongst the Imams of knowledge and religion: “And in it [the Book of Ihya’

‘Ulum al-Din by al-Imam al-Ghazzali] are the words [wisdoms] of the Sufi Shaykhs and knowers who lead the straight path of the heart, which corresponds to the knowledge of the Qur’an and the Sunna. [It also contains knowledge of] And the other rituals of worship and morals that remain truthful to the Qur’an and Sunna”.

From the above extracts, it is clear that, within the Sufis’ ranks, there are those who are deeply knowledgeable of their religion and are from those who speak sincerely and faithfully to the Umma. Indeed, this is what Ibn Taymiyya, who is thought to be an implacable opponent to Sufism, has said.

When the time in which the Companions of the Prophet lived came to an end, a love of the world entered people’s hearts, and they expanded in foods, drinks, clothes, and luxury. In response to this, there arose a group of ascetics (zuhad) who called for Muslims to live simpler, more pious lives. They emphasized the beauty in worship, the importance of self-renunciation, and of directing oneself towards ethical improvement. These ascetics were later called Sufis, among their number were included: Abu Sulayman al-Darani, Ma'ruf al- Karkhi, al- Fadil ibn 'Iyad, Sahil ibn 'Abdullah al- Tustari and al- Junayd.

The first Sufis did not introduce novelty into religion. Rather, they sought what the Prophet (upon him be peace) and his honorable Companions had sought before them. The fact is that some of the Hadith scholars followed the Sufi path; and, providing that they modeled their behaviour on the ascetics who dedicated themselves to purifying their lives of sin, they are to be complemented. Yet, if they followed the deviants and the superstitious; those who tout disbelief (shirk) and reprehensible innovation (bid‘a), their actions are not countenanced. And God knows best.