IF you use the smallest Festool for anything other than sanding dust and small particle sawdust, you WILL NEED a dust deputy and or Festools version.
Once you get into lathe turning, the bags on smallest version will fill up fast. That is why I went with Feins larger vac.
Read this carefully - from a Festool Forum:
Which dust extractor to use with a planer?
www.festoolownersgroup.com
Once you get to sucking in more than saw dust, even Festool forum recommend either separator and dust deputy for larger particles and even going to a larger DC.
Festool IS the FINEST you can get - for what it does, but think carefully about what you will use it for. I have online friends that swear by the Festool vac system, but they use it on fine particles, not chips, plannings, turnings etc. Mighty expensive if it doesn't do all you want it to do because it wasn't made for everything a normal large shop vac or DC system does.
ALSO, do a search for "Festool Vacs and larger chips, turnings and plannings" - you should find that most Festool owners use it with excellent results within its parameters but not outside of it.
AND, look at the specs such as volume per minute or what ever. Compare that to others. Will the Festool meet your turning volume requirements or limit itself to your sanding?
I am NOT against Festool; it is the best, but the Vacs, when I was looking, wasn't designed for what I wanted or needed. I needed more versatility and got a large Fein.