*EDIT* Koden made a point that I tried making earlier but his execution was better.
Of course Creative is saying that. They want to sell more! The question is, why are you listening to MP3's in the first place? FLAC or GTFO. As for hating Sony speakers, I don't think they've ever made anything good in speakers but you can't rate modern stuff. Same for JBL. No manufacturer makes them like they used to.
Car audio doesn't count either as most people there just want bass and nothing else. Not to mention all the reflections inside a car and the ambient noise when driving, it's far from ideal for listening.
Vintage Sony amps are fantastic if you ever have the chance to listen to one.
As far as modern materials in speakers, I don't know what the advantages are but I do know that modern speakers don't sound as good as vintage ones. It's a fact. It's why 40 year old speakers cost so much. A lot of the JBL speakers from back then were built without a budget. Meaning, the best they could possibly make. What manufacturer does that now? It's all about Made in China at a low budget. I challenge you to try and find a modern speaker that's made in the USA, not just assembled in the USA with Chinese components.
Why would you crank headphones that high on a receiver? That's just abuse.
If you ever have the chance, try a real stereo setup. None of this multichannel crap. Somehow get a hold of some 3-way vintage speakers and an amplifier capable of driving them properly. I KNOW for a fact that your Logitech system is highly lacking mids. Those little satelite speakers are fine for highs and the subwoofer puts out bloated lows but you're not getting mids from anywhere. I know, I had a Logitech setup and it's absolutely night and day difference between it and a real speaker & amplifier setup.
I had a HUGE 5.1 Dell setup where the amp/subwoofer was larger and heavier than a desktop computer:

I hated it, even after using it for a week trying to get used to it and tweaking it. I was using my X-Fi card at the time too. It was way too loud and those satelite speakers just can't output a decent dynamic range at all. When you have good speakers, you don't need a subwoofer. They're really only for multichannel home theater enthusiasts that need the big boom and BIC makes some pretty good subwoofers for that purpose.
I'm really not trying to sound all high and mighty and that MY WAY IS THE BEST WAY. I'm just simply talking from experience. I've had a lot of those "gamer" components and I don't have any of them anymore. I've reached a point where I'm 100% happy with my audio setup.

I hear details in music and games that I've never heard before. One minor silly example is how the M16 shot in AA echoes on for several seconds after you fire. I hear things with great clarity. Properly placed and angled speakers allow you to have an experience that I can only describe as up front and personal. You don't have to crank the volume to hear details, it's like the audio is being piped directly from the speakers into your brain. It doesn't sound like it's coming from any specific direction. That's the only way I can describe it.