Sub contract mate
working with someone tomorrow and Friday.
However when i was doing my canvassed work i was doing 850L in a day EASY. Was a godsend then.
The reason i went for an 850 tank is because the 650/850 grippa tank systems take up the same foot print. 850 was like £300 more. Its only taller. So for the sake of £300 it made sense to a get a bigger tank as the 650 would really be about a 610/620.
If i am behind on work, i can fill the tank to say 700. crank up flow to 99 and never worry about water or rinsing lol