The roll is quite big in and of itself. If you fill it with your repair materials, it will be quite bulky and it will not be comfortable to carry in a shirt back pocket. Alternatively, you can hang it on your saddle rail, but the edges and corners will stick out towards the front. Even in my case where I have put the saddle more foreward on the seatpost, the corners stab into my legs while pedalling.
If you plan to have this tool roll to put in a bag, this is perfect, but otherwise it is very limited.