The newest CTMH special is one I've never seen them do in the 6 years of being a customer/consultant. Through the month of March only, if you spend $25 on stamps, you get a FREE block. CTMH will let you choose from a 3" x 3" and 2" x 6 1/2" block. These are 2 of the most popular block sizes, too.
I have seen some of the "other" blocks. They don't have ridges where your fingers can grip the block and they aren't as thick as Close To My Heart's. Our blocks also have the size etched right onto the block so you never forget which size it is. There is also a line on the block, towards the bottom, so that you can easily line up a title or a border stamp.
Read the details here.