It, most assuredly, depends upon "what" you're cutting. I have not had to evact my ass from a Cobra but I have used my sawteeth on my RMK's...(Well" Only "3" of them) for "numerous" tasks. Mostly I cut-n-trim limbs in the woods for clear, un-obstructed shots from my tree stands and ground blinds.
I have "also" had to cut culvert pipes around the lease to rid jagged, raw, sharp edges, etc. and I like "larger" teeth for that chore as they don't "load-up" as readily. With wood, it's not as dangerous and arduous of a task to clear the teeth...versus metal.
Just "my" opinion and work "I" have done with:
* Model #18-5 1/2"
* Model #5-6", with teeth
* Model CC/FT with teeth
...Your mileage may vary...& Coach: I've yet to see a CC/FT with small teeth. Got a pic?
Best, Capt. Chris