Does anyone have experience with Enthral hardshell bass cases or the Aileen music hardshell cases? If so, what is your impression on durability, protection for the bass and overall quality? They appear to be made out of carbon polymer and polymer so I would expect that they are similar to cello hardshell cases. I assume they are not the tanks that the double and triple layer vacuum molded fiberglass ones are and they are probably more robust that the hard foam hardshell cases. If you have one or use one, how are you using it? Thanks.