Dust what dust , i use a sparkey dual blade with a commercial henry vac and its brilliant i even use it to do the back boxessaves so much time and you can get the perfect back box cuts , and very little dust , ive just done a rewire and there was so little dust and what dust was caused by chasing the back box out after , use dust sheets clean the filters of the vac after every chase then theres no problem , if youve never tried it on back boxes do i even cut out singles with it too ,plumb up the chase you want with a level draw 2 lines capping width and cut out down the lines a perfect cut ,was complimented on the chases we did .... by a plumber must have been good lol