I found this product on Amazon and ordered it about a week ago. Didn't know this thread existed at the time. Anyways I've been using it on my Leo tkl for about a week and I only have good or neutral things to say about it.
As stated earlier, it is a few inches short of running the full length of a tkl. If you center the rest under the board, the outer edges of your wrists may hang off the ends. I have mine lined up with the left edge of my keyboard. It fully supports my wrists comfortably at a good elevation. the material is somewhat rough on top but not particularly abrasive. If you have sensitive skin or have a habit of sliding your wrists around then it may be a point of concern. The foam is fairly stiff which i consider to be a positive thing because it ensures that my typing ergonomics will be consistent.
Overall, I am totally satisfied with my purchase. The asking price is beyond reasonable and the utility is there. Unless you are one of those OCD types who can't get over the fact that it is not uniform with the length of a standard tkl or are not a fan of the material (rough cloth over foam) you probably have nothing to worry about.
