I don't think I would buy one.
I've always been a bit uncomfortable with this kind of chiller, as it is essentially a maze of very tiny channels. The potential for clogs must be high, and you would presumably need to flood it with water before use to avoid oxidisation.
The fact that you can't possibly know what is lurking in there after a few uses gives me the heebyjeebies. 3/8" copper tube is one thing, this is very different.
I don't think B3's own blurb inspires much confidence wither:
Cool your wort fast with our new Plate Chiller! Made with 11 stainless steel plates that have been fused together with copper solder, these chillers have small channels weaving their way up and down each plate. This creates more surface area for the wort to travel over, and more time for the water to cool the wort down. The small, compact design allows for any easy intergration into any brewing setup, and takes up less space than any other chiller on the market. Cleaning a plate chiller is a bit more involved than a normal immersion chiller, due to the tiny pockets created by the channels in the plates. These pockets can harbor cold break material, hop remains, or any other solid, and if not removed can cause infection in subsequent batches. The best way to clean is to recirculate a solution of hot water and PBW through the chiller as normal, then backflush the chiller, bringing the PBW through the "Wort Out" side in out through the "Wort In" side. This should remove any particulate that may have gotten trapped by the folds in the plates. Since this type of chiller is relativly new to the homebrewing market, we are unsure just how much solid matter can be trapped in the plates over time, and if a thorough cleaning can break any of the solids free from the corners or not. 12.5" long, 3" wide, and 2" thick. The wort inlet and outlet is 1/2 Inch Male Pipe Thread, and the water in and out is 3/4 Inch Male Garden Hose Thread.