I use a couple of shop vacs too as I can't justify replacing them when they work well and actually have more power than a Festool vac. There are other Festool tools to buy! I have a Dust Deputy mounted on my larger vac, and use bags that you can buy from Home Depot that will help keep the filter clean for my small Ridgid vac. Originally I bought the little vac for cleaning up rodent poop and debris in the attic, but wound up really liking it for many other uses. Also run an auto switch on my larger vac. With the Bosch hose the costs are getting up there, but I was able to spread the costs out over time. My larger shop vac came with an attachment that has a variable slider on it to decrease vacuum, which I put before the Bosch hose when I want less suction. The biggest benefit a Festool vac offers is they are quit!
Someday I will buy a CT36...