Yes, that is the general consensus. However, they should not be lacking at all.
That's because laptop audio is completely pathetic. If your laptop is your main PC, you should look at something like the Audigy 2 NS I think it is? Whatever, it's basically an external Audigy 2 ZS.
As far as 5.1 headphones:
Generally, a gimmick. If you want real surround headphones you're looking at something like very expensive (several hundred dollars) headphones which have their own surround processor, which is like the size of a very mini-ATX case. They're pretty awesome, but regular stereo headphones in the same price range will hand them their own asses on a silver platter.
If you have a binaural recording, NOTHING is better for sound positioning than headphones. NOTHING. Binaural recordings are recordings created with two microphones and a dummy head. It's recording the sound exactly as how it hits your ears, so when you play it back, you can have sounds near, far, up, down, etc. However, there are VERY few binaural music recordings, and obviously games aren't single recordings...but 3D sound APIs such as A3D and EAX attempt to simulate this in real time. It's not a mind-blowing effect by any means, but it's easy to tell what's infront of you and what's behind you, regardless of headphones.
That said, some headphones are still better for gaming than others. Headphones with a wide soundstage are good for gaming. The term "soundstage" comes from stereo speakers, where you get an imaging effect from well recorded tracks, such that you can hear where on stage each performer might be. Vocals sound like they're coming from the middle (play from both speakers), drums from the left side of the stage (all left speaker or mostly left speaker), etc. The same effect is carried over to headphones, except it's not quite an in-front-of-you sound so much as an all-around-your-head sound.
Basically, headphones with a "wide" soundstage means the imaging effect is wide and open sounding, not collapsed and narrow. The wider the better, for gaming. Headphones with poor imaging also typically have poor instrument separation, which is, quite simply, the ability to hear the differences between instruments. Some headphones, even very expensive ones, have ****ty imaging and instrument separation, I guess some people prefer it (Grado anyone?). I for one, can't stand it. It sounds completely unnatural. And you don't even need to be some crazy audiophile to hear it. Ten minutes with a pair of good, wide open sounding cans and you'd know what I mean.
But anyways, what's your budget? And do you require a microphone? Would you be willing to sacrifice the convenience of a headset for regular headphones + a clip-on microphone? It's a common suggestion since headsets are of sufficiently less quality than equally priced stereo headphones. The Sennheiser HD280, for example, is a fantastic headphone for music, gaming and even studio monitoring (around 80 dollars). They have a version with a microphone on it, but it costs an extra $200! The mic needs a preamp, you can't even plug it right into your soundcard (at least not without good results, quality-wise). Sennheiser could tack on a $10 microphone that sounds good for speech and you'd have the best damn gaming headset on the market. But instead they designed a new line which isn't really that good. I dunno.
One other question - open or closed? Open-air headphones (or just "open" nowadays) are headphones with an open back, so sound leaks out (usually very little if you listen at reasonable volumes), and sound also leaks in. They typically sound better, because sound waves from the driver (speaker) in the headphone isn't reflected back towards your ear. Such an effect is sometimes desirable, sometimes not (as in the case with open headphones). Closed, or sealed headphones, leak little sound and let less sound in. Some isolate you from the outside world better than others. The aforementioned Sennheiser HD280, for example, isolates you a good 15-20 dB of noise, it's suitable for use on airplanes.
Oh, and I have a story about 5.1 headphones. I bought the Zalman 5.1 headphones a few years back, thinking they would be a decent replacement for my Sennheiser HD414s, circa 1968. Granted, those were hi-fi headphones at the time, but I figured the Zalmans would have to be at least as good. Dead wrong. They blew. Horribly. A 35 year old pair of cans destroyed these 5.1 gaming headphones, both in terms of sound quality and in actual usefulness for gaming. It was absolutely pathetic. As you can imagine, those pieces of junk went straight back to the store. I mean, just think about it. You're paying $60 for what, 4 or 6 total drivers? You're serioulsy cutting costs to get a lot in there. Plus it doesn't even make sense to call them 5.1 headphones anyway, since the fifth channel is a center channel and the .1 is a subwoofer, neither of which are at ALL useful for headphones.
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