What does Comcast do well? I use Comcast for both my internet and television. I think that the thing it has going for it is options. There are quite a bit of packages to choose from. And my internet is usually pretty fast.
What does Comcast not do well? Oof, where to start. So many different issues over the years with Comcast. First of all, the customer service is always 50/50. You just never know what you're going to get. I usually try and get billing and changes handled over Twitter so that I don't have to wait on hold for a long time. The pricing is also a lot more than I'd like to pay, but I don't know anyone who doesn't think that. I only wanted basic cable because I stream most of my shows, but for some reason, to get the best price for my fast internet (I work from home), it was better to include more channels and HBO. Makes no sense. I should only have to pay for what I need, and be able to keep it affordable.
What do you wish you had known about Comcast before using? Nothing really. Their reputation proceeds them. Everyone complains about the customer service and the prices. But I am self-employed and work from my apartment, and I only have the option of Comcast or ATT. The prices are generally about the same, as is the customer service from what I hear, so I just keep sticking it out. Not having options is hard.
Have you used a competitor to Comcast? If so, how does it compare? It's been probably 20 years before I have used anyone other than Comcast, so I don't have much first-hand experience with anyone else. No one seems happy with the customer service or price of their cable, no matter who they're with. It's a shame.