My Hydramaster TM has bags in the waste tank and yes you do get a bit. I only check every three days and most of the time there is nowt in it
I love the inline filters no scrabbling around in the back of a hot van after each job to clean the bags out.
But alas my machine has just been sold
So its back to electrics and the DF method for me- just have not got the work for a TM these days