According my research and experience till now, self enquiry seems to be the quickest method to dissolve the ego. Leo also advises one hour self enquiry. But Ramana Maharshi says it can be done all day, any time even during work even in sleep after some practice. It's the most simple and direct method. If you go on the traditional path of yoga in camprison its gonna take much longer. Instead of improving qualities of the ego, ego is being direct attacked in the self enquiry. When Eckhart Tolle had the experience on his awakening night when it was self enquiry. This has been confirmed my Leo, Papaji, Mooji, Ramana Maharshi. There is a great video down below about Ramana Maharshi and his teachings.
My mind is very quiet after a week of self enquiry. I have also had an enlightenment experience few months just for 20 seconds may be and it has kept me going till now that's how powerful it was, it was also after self inquiring question when I look at it now.
I hope it help you guys
https://www.youtube.com/shared?ci=trJrl72RDpg