I used the 4-7/8 triangle (55002) the Half Square 3in finished triangle (55009) and the 3 1/2 square (55006). I started with just the 3 1/2 triangles - but the other 2 sizes worked in perfectly.
I got the starter kit and they said they mostly worked together. They work really well together! I can't wait to get the tumbler.
Also - take a look on You Tube for LoveBug Studios. She has really great videos and tons of good ideas. The one about marking the die was really helpful and it seems it helps not waste fabric.