Ive used it on the last cpl jobs and I completely agree with Al. I can't believe i used to work out of a bucket with the damn pole and applicators etc... Soooo consistent and way easier on the body.. not too much faster, but whos in a hurry to save 15-20 minutes anyways.

i use old carpet bonnets and i have used it with rustoleum stain sold at lowes, even dark walnut. works fine. now i will have my eye out for some free plush carpet scraps.
Bob

While you are cutting the discs from clean carpeting from a
seldom walked on area, save the part that will not make a complete disc and
cut some foot sized skates. You can slide around with these under regular shoes.
Then when you reach the doorway just step off to a clean area.
Leave a couple of pairs for the clients to move through the area if they are needed.
When taking out used carpeting you can probably give it away on free cycle if it is not cut into little strips. Clean padding can be used under area rugs to make them feel more luxurious and help keep the fibers from getting pinched. The area rug will last longer with a pad under it.
Please recycle, our world needs it.

Can you use water based stain to do this method? If not why

Some water-based stains I have used will not work with a buffer and pad. The buffer warms the floor and stain from friction and this will pill the stain it dries so fast with a buffer.
The oil based stains have a slower drying solvent and oil mix.