not to mention the ported boxes are usually tuned very poorlyA lot of prefab boxes are made as cheaply as possible. Thin MDF, poorly glued together, screws aren't predrilled so there are cracks, carpet not glued on properly etc.
You don't need screws to build a box, the glue is good enough, if done correctly. People build boxes without screws all the time, that box was obviously just not properly constructed.Prefabs ****..
My buddy has one for his 2 15s and it started rattling really bad. Come to find out it was coming apart and they didn't even screw it together it was only held together by glue. I screwed it all together as a temp fix and im going to build him one myself. As said earlier its even cheaper to build your own.
Just like stated above, a chemical bond is stronger than a physical bond.You don't need screws to build a box, the glue is good enough, if done correctly. People build boxes without screws all the time, that box was obviously just not properly constructed.