I have been told 2nd hand that it would be a good thing to go ahead and purchase the foam marker when purchasing the machine. I would like to know if this is really necessary or if in time it would be more of a nuisance? I have a PG and for awhile I used blue tracking dye. However, after time(and lots of mess) I have become very adept at spraying without it. Would this also be true with the Z-spray?