I just bought S.W.A.T. DVD for P150 on sale in Astrovistion. It was released by Magnavision, and is DVD5. The packaging was beautiful, and even came in an impressive box. At the back, it said "anamorphic widescreen", Dolby Digital 5.1, and several special features like deleted scenes, trailers. I thought to myself, this must be DVD9. No way they can fit all of that in DVD5, right? Unfortunately, it was a DVD5 disc.
The movie itself, thankfully, was watchable. I'd give the video a 6.5/10 for quality. In my 32" screen, it was definitely not as sharp as a DVD9 disc.
The soundtrack was indeed 5.1 but sounded very compressed, like a 128kbps MP3. I'm no audiophile but could compare with other DVD's with DD 5.1. It sounded like "night mode" was turned on in my player, even if it's not.
The menu looks horrible. Literally VCD quality, with super blocky / pixellated pictures and washed out colors.
Lesson learned: unless the label specifically says DVD9 or "dual layer", you can't really make assumptions. Even at the sale price, I felt disappointed.