I love Style Arc. I have more than 50 of them ... probably closer to 60. I've purchased directly from them, via Amazon and Etsy. I admit it's crazy as it is unlikely I will ever use half of them. The ones I've made have fit pretty well and certainly better than most other pattern brands with minimal tweaks. Even though I've only made a handful of them most of the one's I've made have been made multiple times.
In my experience SA is well drafted and if you match the notches you will be fine in spite of the sometimes terse directions. Those directions are best used as an order of operation.
Rene, I'm pretty sure SA has far more than 120.