Well it's not that it's bad, its just troublesome. That happens to be the best phone modem (EMTA in the biz) I have seen out there, with the gateway not locked down. Also it has 8 channels down, and since it's only put in during proffesional phone installs, the signal specs are usually pretty tight(good).
Where they become a pain is in troubleshooting. If you call for support, you have to call from a phone other then your house phone, and if you want to reset it, you need to use a paper clip. Also, since the modem needs to be near your router, the phone part of it can't be in your basement, which is best. Thats because that is usually where your phone punchblock(think circuit breaker for telephone) and its better to have your phone modem connected directly to it. On the other hand, it's one less splitter you need in your set up, since you don't need to split the coax between a phone modem and internet modem. So its a double edge sword.