I spent up until this week working in a larger sketchbook. But it was a challenge for me to fit the paintings into my 30 minute designated time slot. I've learned from experience that if I take any longer than that I start to get stressed out and I can't move on with my day. It was hard for me to admit that I couldn't do it. I'm now back to using a 5x8" sketchbook and it all seems so much more manageable and I'm happier. I will be doing larger paintings but just not with a time constraint around them.