I wouldn't trust my ISP with my router, but i bought my own cable modem off their approved list to avoid rental fees. However, if you look more deeply into that

I wouldn't trust my ISP with my router, but i bought my own cable modem off their approved list to avoid rental fees. However, if you look more deeply into that, it's an approved modem because the ISP does have access to full management of that hw down to fw upgrades - and to give some credit, the modem portion does seem to work seamlessly.