Thanks for the correction about the CM1000 chipset.No. The DOCSIS 3.1 modems Motorola MB8600, Netgear CM1000, and Arris SB8200 all use Broadcom chipsets, which are the best in the market.
The Netgear CM1000 is a good modem and probably the easiest to use of all three. If OP wants to attempt to use it with Spectrum after they indicated they are in practice open to provision a non-approved modem, then that's great for them. Worst case scenario if they buy it from Amazon, they can just promptly return it and get a CM600.
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