had to have the Simplicity Rotary Strip Cutter. Useless for me. I love the Simplicity Bias Tape maker though. It irons the tape for me and I find that priceless. I love my bobbin winder. Works great for my Brother machine.
I like the "lipped" rulers, they don't slide as much. I have a triangle ruler I rarely use, but I'm always using my 12 1/2 inch square to square up blocks.
I love my spinning mats, I have both sizes. I have a combination pressing mat and cutting mat with handle I don't use at all. A friend ironed on the mat, now it is warped, but usable. Just not useful.