Most people have been fairly happy with the seidon. Not a bad rig but the h100i will outperform it slightly. The only one that really compares is the NZXT kraken x60 that usually comes out on top.
All 3 are decent though I doubt you would have a problem with any of them. IMO x60>h100i>240m
http://www.guru3d.com/articles_pages/cooler_master_seidon_240m_review,11.html
All 3 are decent though I doubt you would have a problem with any of them. IMO x60>h100i>240m
http://www.guru3d.com/articles_pages/cooler_master_seidon_240m_review,11.html