Almost every Saturday a friend in Chicago and I compare his Ragozin Sheets to my Thorograph.
Sometimes there are significant differences. Sometimes Sheets provide the best info, sometimes Thorograph does.
Bottom line is both are better than anything else available, and when I have winning days with Thorograph I am happy I use them, and when he has big days with Sheets, I am sorry I didn\'t use Sheets. Thorograph is less expensive but I was schooled on Sheets years ago. If you believe there are significant differences overall, let me know what they are.