Bestem is known for being good value, but not necessarily high quality. Bestem manufactures a variety of products, but our experience has been limited to two product types. The first is the T-Box top case. We have use this product for over 10,000 miles including a cross country trip and significant commuting duty in all types of weather. While there is no argument that a box from a company like Givi is of thicker more durable material, the T-Box has worked well, has not had a failure of any kind even when overloaded, and has withstood significant mileage and vibration. The 39 L box holds two full face helmets as advertised, and in our case, has an additional brake light built in, which has been wired to two different bikes.
The second type of product is a luggage liner. We have recently purchased a pair of these for the R1200RT, with the thinking that these are not heavily used, and will help to keep things from falling out of the side-loading luggage. There is a large variety of solutions for this application, with well-known names, and prices which are orders of magnitude apart. Upon receipt, we were immediately impressed with the quality of the bags for the price. They are thick and hold their shape fairly well. They have quality zippers, straps, and even have a clear pocket for labeling. They also appear to have a reflective strip for visibility, which seems a bit strange, but would make them useable even as throw-over soft luggage if needed. More over time, but these appear to be quality bags at bargain prices.