Did I make a $130 mistake?

[Dennis McDonaugh]

I'm going to keep using it. It won't be the first tool I've buggered up if it burns out the motor.

[Andy Pratt]

I would have absolutely no worry about using a full kerf blade, and I've been using one on my makita 12" scms for over a year now. I have cut 12" 8/4 jatoba with it in one pass and, although it is about all it wants, it works fine. Making sure it is the right tooth geometry for the type of material you are using is far more important than the tk/fk debate.