all those aren't good with mediacom the net gear has no good fireware and bonding issues on mediacom even if its comcast cert..
the surfboard 6121 doesnt have good bonding the previous version the sb6120 has firmware push from mediacom to fix bonding
the others i dont see them on the internet support so you may be good to go..
as for buying the modem i would buy anyone i see.. they let you use any docsis 3.0 but you wont know if it will bond till you hook it up... and do speed test for weeks ..
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from »mediacomcable.com/CustomerSuppor ··· =11365.0
We support the following Docsis 3.0 Cisco modems.
The following Netgear modems