Manny:
I enter the conversation late, but if you haven't yet made a purchase, it's important to check which cable modems your cable co. will support. Most cable co's have lists of those modems they will support, and while that may seem trivial, in order to properly provision whatever modem you purchase, your cable co has to have the proper firmware to download to the modem. So check your cable company's list of supported modems, and make sure they support whatever you're considering.
I know that both TWC and Comcast support the SB6183, and since I'm on TWC, getting their 300/20 tier of service, I purchased my own SB6183 early in 2015 (right about the time TWC increased speeds to what they call "Maxx"). The 6183 has functioned flawlessly.
Be forewarned that if you are on TWC, the SB6193 (which is a 32 x 8 modem) at this time is NOT supported by TWC, and from what I know, in order to support it, they're going to have to get rid of close to 100 duplicate digital or unused tv channels to create the additional 256 QAM download streams needed to provide full capability for this "gigabit" modem, and that isn't going to happen, at least not on TWC for quite a while, possibly not until after the Charter merger/takeover comes to fruition (assuming it will). According to several people who have reported on the TWC Forums about their experiences with the SB6193, TWC doesn't have the proper firmware package to properly provision the modem, and at this time, you'll be limited to a max download of 100 Mbps, far from it's potential capacity, and worse than the performance you'll get from the SB6183. So if you're on TWC, at this time there's no point in buying the 6193, and you should go with the 6183 instead.
I believe that TWC also supports the Netgear CM600, which is a 24 x 8 Docsis 3.0 modem, which is capable of speeds close to, but not quite gigabit speed, but even so, all you'd be getting with the CM600 (which costs about $40 more than the SB6183) is something that might eventually be useful for speeds greater than the 300Mbps download which TWC currently offers. If you're trying to "future-proof", you probably won't see that future (in terms of higher download speeds) for quite a long time from TWC. A 24-channel modem could deliver 912Mbps downstream, and 32 channels could boost that to 1.2Gbps. But again, sadly, neither TWC nor Comcast are offering speeds anywhere near that because both are bonding only 16 channels down.
Also, keep in mind that the 6183 is capable with the 16 bonded channels presently provided, of reaching speeds of around 686Mbps down which is literally twice the max speed now offered on TWC, but again, TWC isn't going to offer anything faster in the near future. Even if they doubled their download offerings, the SB6183 is going to be perfectly adequate for the foreseeable future.
For the money, the SB6183 is a no-brainer if your cable co supports it. I highly recommend it as a first-rate, top-quality product.
