Is not good for me. I spent about 40 minutes working with it in my unventilated basement building my SR-71 model. When I came up afterwards, I was shaky and clumsy, and my eyes were very dilated. I was still able to chat with a friend on the computer, but it wasn't easy. At my mom's suggestion, I rode my bike for a few minutes, and that certainly helped.
From now on I'll have the door open and only do a little at a time.
Unfortunately, I didn't have any time to work on rockets today because of homework. I did, however, do more simulations of my rockets on my calculator. Soon I'll have sim charts for every rocket I own.