I was a Fimo Classic & Premo girl originally. Then Fimo changed it's formula a little and reduced the baking temperature so now, I'm mostly a Premo girl although I still have more than 40 pounds of old Fimo to work through.
When I began caning the stiffer, more dense clay gave me more control over my canes. You got crisper lines and shapes didn't melt in your hands. These days the combination of the two lets me quickly work up complicated canes that are still crisp and clear:
For the beads I make, most of the bases are Premo these days because I like how fast it is to work up. I also did a whole lot of colour chips with it which are posted as charts on my website...
This means I'm able to replicate colours from formulas and most of the bead lines I make use this. These guys are from that middle chart, for example (3 Turquoise, 1 Fuschia):