After a decent amount of research I chose this mat from Staples because it was reasonably priced came without the "tongue" which is the type more commonly desired and was of a decent size that fit my "goldilocks" needs (not too big not too small). It unrolled easily (except for the 3 small gashes on my knee which are healing quite well thank you!) & once I laid it out & put the desk chair & a book/ream of paper on the strategic spots within 2 days it was completely done. I was truly impressed - it usually takes much longer more weight is needed & there is a remaining slight ripple somewhere always!).