srtie4k

Holo
I rent my modem from my ISP. I am also a networking major. I've learned that having your own equipment isn't a great idea in the long run.
 
The main advantage to paying an ISP for a modem is that you are never responsible regardless of how that modem fails, whereas a modem you own is your responsibility to authenticate, update, and maintain(or replace in the case of failure) not to mention if a new standard comes out your tech becomes obsolete. Twice now my ISP sent me a new modem due to improved firmware and hardware with a better revision. They sent me an email stating new modem came in, and all I did was plug it in.
 
With that modem being 80 bucks it would be at least 2 years before you recoup the cost, and if you change ISPs and have to move away from cable, that modem becomes obsolete.
 
Also, I am unsure what you mean by doing your own ports as that makes no sense to me. I do my own port forwarding, and QoS on my personal router which is running DDWRT. My modem is simply that, it modulates data from my ISP to my router, and from my router back to my ISP. Otherwise, all routing, filtering, ACLs, and static routing paths are inputted by me and managed at my own discretion. My modem's routing functionality has been disabled, it literally forwards everything including the IP to my router, and does nothing more than passthrough for data being sent.
 
If TLDR, not worth the investment realistically.
 
Feel free to PM me if you have any networking questions.

I disagree entirely. And FWIW, I was also a network administrator for a number of years.
 
My ISP (TWC) began charging me $6.99/mo for modem rental only a few months ago. Cable is cable is cable, all large cable ISP's use the same DOCSIS specs for handshake, and all DOCSIS modems are backward compatible, so really any DOCSIS 3.0 modem will work with any large ISP. And at $7/mo, after buying my own for $80, I'll break even in one year. Furthermore, if you consider that broadband speeds have increased in a downwardly exponential curve (i.e. have nearly flat-lined) in America for the past several years, the chances of your ISP pushing beyond the capabilities of an average DOCSIS 3.0 modem within that break-even window is absolutely zero. Even if it takes you 2 years to pay off your modem, you'll still never see faster cable throughput speeds than it can support.
 
OP, buying your own cable modem is 100% worth the cost. The only thing I'd change about your original post is your selection of modem. This is the one I bought, and I am EXTREMELY happy with it thus far. It supports stupid fast speeds (300mbps down, 100mbps up), is rock solid stable, and is pretty cheap:
 
http://www.newegg.com/Product/Product.aspx?Item=N82E16825390001&Tpk=motorola%20sb6141
 
Keep in mind, you'll need a dedicated router when you buy a dedicated modem. Your first post didn't seem very clear, but it sounds like you might currently have a combination modem/router that you're currently using, which neither the modem you linked to or the one I linked to will replace 1 to 1.