I've not used his product, and I am very skeptical of the practicality
and utility of any plastic tube versus paper, paper/cardboard,
bamboo, or other non-plastic and/or non-metallic tubes.
Let me explain. Many, many moons ago, McDonald's gave out cardboard
straws with their milkshakes. They were the "perfect" size for Osmia,
7mm inside diameter, and about 6 inches long. Better than that, they
were available in bulk, so one could pick up a dozen or more when buying
one milkshake, or slip the manager a few bucks for a box of 1000.
In the late 1980s, they switched to plastic. Plastic did not work as well,
moisture condensed inside the tubes, and hatch-out rates plummeted.
Dr. Suzanne Batra of the USDA ran some tests, and verified that plastic
was contra-indicated for Osmia tubes.
Perhaps the plastic used for this product can "breathe", but the basic
problem I would see with them would be cleaning the things. The paper
tubes are expendable and dirt cheap, so one can replace them every
year (when washing cocoons) or replace them when they start to look
"drity", re-filling the cardboard tubes (pretty cheap) as required.
But how and when does one clean these plastic tube sets?
Given that the tubes are always either holding cocoons, or are
"in use" by active bees, I don't see when one could do this.
Further, the claim made by this vendor that cardboard tubes can
be penetrated by parasitic wasps is false. The cardboard tubes
sold by Knox Cellars and others provide excellent protection.
(The old McDonald's straws were too thin to protect against the
wasps, but they haven't been around for decades.)