Yikes! In 30 years of computer experience and knowledge, this has been without a doubt the most negative experience to date.
Based on tomshardware review, and tons of searching (even knowing the difficulties of others in this forum), I decided to purchase the Medusa 5.1 Progamer headset from Medusa-USA (NOT a US distributor, but more on this in a bit).
I received it, really liked the look and comfort (though quite heavy). I hooked everything up (onboard sound), went into a couple of games, and experienced the same as most others - no bass, very, very tinny sound from both rears and front. Also quite a bit of feedback from the mains. I tweaked, I played, I even customized cables for bass/center crossover, and never got positive results in two long days of tinkering. So, I contacted their tech support department, who told me these headphones would not work with onboard sound solutions. I then bought X-FI Fatal1ty Extreme Gamer soundcard, went through everything I could find (another day of troubleshooting), and still had the same results. So then I hear from a longtime friend who went through the same experience. Speedlink told him that they do not guarantee the same results with all games - some will simply not sound correct. Wish I had talked to him before.
I made other enquiries, thinking that the non-progamer would be better. No response, so I decided to RMA this set. Here's the kicker. It cost me $29 to ship these back to the UK (NOT to Medusa-USA!), and $9 and change to receive them. We are all aware of the policy that we eat shipping. At the end of the day, it cost me almost $40, or 25% of the purchase price, to determine just how crappy this product is.
How can you advertise as surround-sound, when there is a very distinct difference when sound switches speaker drivers? As indicated by the rather arrogant owner, the tinny sound in back speakers is 'by design'. What??? How is that to contribute to an immersive surround experience?
Oh, and the 'Vib' function? About the most ridiculous, distracting and uncomfortable "feature" yet experienced. When we hear a loud noise, or low bass, do our ears vibrate naturally? Just silly.
Sorry Speedlink and Medusa, your product stinks. A very expensive roll of the dice for most, given the fact that shipping must be back to the UK. A product that, if it works at all, must take great steps to get it to even function with arguably the best soundcard on the market, and a product that may not work with your preferred game.
By the way, I replaced these with Sennheiser PC166 - outstanding, incredible.
I hope this helps others fooled by the hype.