You don't usually notice a difference when you go to a better quality headset. You only notice when you go back.
Unfortunately I have no experience with Corsair, so my opinion is mostly invalid here, I do however have some experience with Sennheiser. So I went from a Siberia V2 to a Sennheiser because it was uncomfortable and the microphone sucked. Unfortunately the Sennheiser was still uncomfortable, but the microphone was excellent. The soundquality of the headphones is also quite good in direct comparison to the Siberia V2s. Due to the Sennheiser being too uncomfortable for me I have since moved on to a beyerdynamic Custom One Pro (with a desk mounted Blue Snowball) which has even better sound quality due to it's more closed off design there's not so much interference from background noise as with the Sennheiser. It's still very uncomfortable after an hour of wearing tho.
DISCLAIMER: I have the kind of ears that make everything but in-ear plugs very uncomfortable, that's why I just use the best sounding (cheapest) headphones I can to make it worth the pain.
If you have normal ears Sennheiser Headsets are probably comfortable, offer great sound quality, headphones and microphone and the models you list come with a really good external sound card (which I still use with my custom one pro).
tl;dr Sennheiser -> Pretty good