I and some others here have had the best luck with "Super-Adhesive Nylon Hook and Loop" sold by McMaster-Carr, whose online url is:
http://www.mcmaster.com/
Search for Super-Adhesive Nylon Hook and Loop via their Search Box. It may be found also on page 3212 of their online catalog. McMaster-Carr sells the hook and loop together or separately in 1" and 2" widths. Most of the original, factory-installed velcro peeled off the inside walls of my 3124KS. Initially I replaced the strips with "Industrial Strength Velcro" but the adhesive bond quickly failed on this brand of velcro. After applying the Super-Adhesive velcro 3 years ago, none of it has come off. There are a few areas where a strip is buckled - probably from expansion due to the summertime heat of our valley (our TM is kept outside).
I'm not familiar with using staples to keep the velcro strips attached. Ours don't have any staples driven through them. Staples may have been used in an attempt to keep the velcro from coming off.