VPI Record Cleaning - Does Bidirectional cleaning really make a difference?

Inna,

I thought the mo-fi brushes were a copy of the Disc Doctor brushes?

Taters,
You are probably right.

inna,

I have a MoFi brush and two Disc Doctor brushes and they are essentially identical. As for your concern about scrubbing the record with these brushes causing damage is concerned, you seem to be thinking that the bristles of the brush actually can get down into the grooves, or that the dirt is abrasive. Neither of these is really likely, but I will take it under advisement. I have owned my HW-17 since new, purchased in 1990, and have used it on literally thousands of records. None have been hurt as far as I can tell. I think we can agree that the reverse motor feature is nice to have, however, I stand by my original post that it is not essential. As far as cleaning fluid goes here is a recipe that works quite well: 1 gallon of distilled water (pour out 1 pint), 1 pint of isopropyl alcohol (99% if you can get it), 2 drops of liquid dish detergent, mix well.

I would assume that some dirt particles are abrasive.
I only tried Audio Intelligent three step so can't compare to other fluids.
I also had a few records cleaned by Audio Desk ultrasonic with pre-cleaner and water on VPI 17 before that and double rinsed with water and vacuumed after. I did compare the same albums the same pressing with the records cleaned by me on Okki Nokki with Audio Intelligent, double cleaned and double rinsed with water each time.
I heard no difference, both were very clean. However, I don't have a high resolution rig so perhaps there is a slight difference. Still, my system is very sensitive to small changes of whatever, so resolution is not bad at all.