I wanted to write on this topic before Sunrocket went down. But even as it is going down, it's still earning me money!
Ex-customers get special promotions. I get 6 months free if I rejoin my old phone company! So I'm earning money instead of just saving money. Same for satellite. If I switch back to cable TV, I'll get about $300 cash I guess, to pay for the satellite contract. But I have no contract! I'm tempted, but I'm just too lazy.
If I rejoin cable, I get $10 off since I had internet already. I get $5 off from satellite since I will have a proper phone line for their box. So it's not a pain to rejoin. But even with these discounts, I like the extensive features of VoIP, and I wouldn't switch back if Sunrocket is still in business.
Other VoIP companies offer to buy your Sunrocket contract, free adaptors, free phones, or port your adaptor to their service. Some have even more features like bridging your cell call to wireline calls.
The only regrets? My cordless phone become obsolete. I should have got just the adapter for free during promotions. Though the money I saved and earned should more than cover the cost of the subsidized cordless phones. But they are pretty good wireless intercom systems and wireless monitors!
BTW, I think what killed Sunrocket is the launch of T-mobile dual mode Wifi cell phones.