I would hope that PowerDVD only kicked me to basic mode because it's an old version...that seems like a pretty huge bug to not fix. I'm assuming it's because it couldn't use DX9.
As for system resources, imo 15% is still way too much for it to need unless you have a really weak CPU. I have DAPlayer running right now, playing a blu-ray disc, and it is currently using... 0% CPU and 32.256MB of RAM. I never actually watched the system resource usage with PowerDVD, but any time I started it, if I forgot to stop FAH running beforehand it would take about a full minute of Windows trying to figure out WTF it was supposed to be doing before the video finally started playing, and during that time my computer is entirely unresponsive. Even if FAH wasn't running it would take around 20-30 seconds. In contrast, DAPlayer starts right up in less than a second and takes about 2-3 seconds to load the BD-ROM. It's also a much sleeker, simpler UI that, imo, looks a lot better than PowerDVD's cluttered UI.