Need to upgrade C300 firmware, ISP refuses to help, Netgear support won't help

I have a similar issue (and in a similar situation with being outside of the 90-day warranty window) with a C3700 Router with Cable Modem and Comcast/XFinity. I too have been in the quagmire of not taking the pay for support option. On the other hand the cable provider says that we have the latest version of the router firmware. How do I qualify and confirm that this version is the right version? How do I defend myself with their technicians when they point the finger at the customer owned router/cable modem? I have been getting intermittent disconnects several times a day every day for the past four months. In order to avoid having to call their technical support (a total waste of time) I have been putting up with it as it lasts only a few seconds to a couple of minutes, sometimes requiring me to unplug the power to the router, waiting a few minutes and then reconnecting it. It is interesting to me that being a Netgear owner and user myself and recommending Netgear products to many people (including the one that owns this C3700 device) how Netgear fails in providing quality customer service and technical support for free when things go wrong and a customer is outside of the regular manufacturer warranty on a product that cost over $100 and requiring end-users to pay for support at a cost of almost half the cost of the device for 30 minutes of support. Ok. I get it. Support costs money. How much does losing a customer cost you? How about a hundred customers or a thousand customers? I do not have the time to email your technical support folks. I do not have the time to spend sifting through these forums for the answer or more appropriately a VIABLE SOLUTION to this problem. While I understand the challenges on both sides, the customer is NOT the enemy! That is EXACTLY how I feel. I will remember this experience when I get ready to purchase my next new router in the next couple of months.