I did several $5 quilts at the LQS (you pay $5 for the first block, and if you make the block and take it to the meeting each month, you get the next block free), and they all required the Marti Mitchell template sets. Since the LQS has stopped doing them, the templates sit in their little bags taking up space. One template that I didn't buy, because I thought it would really be a waste of money, was the log cabin template.
I have two of the 60 degree templates (for use in OBW and hexagon quilts) and the Tri-recs, which I have used in two quilts. I have one of the binding templates, but have never used it. I have looked at the twister template, but decided I'd probably never make one. It just seems like too much wasted fabric for me. If I ever decide to do a double wedding ring or a drunkard's path, I will definitely get the templates for those, but I don't like doing curves, so they aren't even on my bucket list. I bought the dresden plate template, and I have used that to make a tablerunner.