Based on advice, I did not choose to rent their modem and bought my own from Amazon: Motorola SB6121 and it worked great. There is an older model SB6120 that is a bit cheaper, but my friend had problems. Please check with the technician and confirm that those models work in your area.
Today, they came in and installed it for me. The overall process worked fine except for three complaints:
1. They kept calling for confirmation. In the past week, they called so many times for confirmation, 3 days before, yesterday, and this morning. I understand that some people might be forgetting things very quickly, but I am not that type of people. Plus, I have confirmed at the first call already and they are still calling as early as 7am in the morning! Since I did not get this morning's phone call, they left a message and said I would have to reschedule it, WTF. So, I ended up calling them again so they can send the technician in without rescheduling.
2. Some technicians are un-professional. I am quite busy with work and life, so my appointment is 8-10am, earliest I could get so I don't miss the work. For the first appointment, the technician waited outside for 1 hour before he came in (I saw his van and went out to tell him I am ready, but he kept sitting in his var for another half an hour). When he came in, I showed him where I want the setup and the pole to pull the signal from. He shrugged his shoulder and said "it will take at least 4-5 hours". I said I thought it'd be only 1-2 hours and I had no choice but to reschedule. Somehow from the look on his face, I felt that he did not want to do installation (bad mood, lazy, etc.) and I am fairly pissed. If you don't want to work, then don't come to waste your time and my time.
Today, another technician came in and he is much better. He finished the whole job in 1 hr and told me the previous technician "must be lazy".
3. The installation process forces you to install the desktop installer to activate. After the hardware is set up, I hooked up my wireless router and was directed to an activation page, which asked me to create a new Comcast user account. But the last step is to install Comcast desktop installer and there seems to be no way around according to the technician. (Update: according to my colleague, you don't need to install it, just restart the modem, shutdown router, connect router with modem, start the router. But I did not try this personally, not sure if it would work.)
The installer file is "ComcastDesktopInstaller_MMF3.pkg" in my case. I uploaded it online if you are interested. Luckily I unchecked "install browser toolbar" option during installation. People are suffering from this toolbar since it hijacks browser preferences and homepage. If you are the victim, please follow instructions on this page to get your previous setting restored.
The installer file is "ComcastDesktopInstaller_MMF3.pkg" in my case. I uploaded it online if you are interested. Luckily I unchecked "install browser toolbar" option during installation. People are suffering from this toolbar since it hijacks browser preferences and homepage. If you are the victim, please follow instructions on this page to get your previous setting restored.
After the network is up and running, I want to uninstall it but could not find much info. I did my best, and my conclusion is it might not do as much harm. It executed some Ruby scripts and installed some crap on the desktop, which you can delete easily.
Cleanup actions in summary:
1. Delete the two website shortcuts installed on my desktop.
2. Delete ~/.cim_install_log.
3. I am not familiar with Ruby, but the scripts seems to just create Xfinity bookmarks for Safari, Firefox and Chrome. For details in the script, see the gist below.
4. Besides those, I did not seem to find other suspicious malware or unwanted junks.
Cleanup actions in summary:
1. Delete the two website shortcuts installed on my desktop.
2. Delete ~/.cim_install_log.
3. I am not familiar with Ruby, but the scripts seems to just create Xfinity bookmarks for Safari, Firefox and Chrome. For details in the script, see the gist below.
4. Besides those, I did not seem to find other suspicious malware or unwanted junks.
Detailed checkups for the Comcast app:
1. Did a grep for "comcast" and found a log file in home directory: ~/.cim_install_log. It contains all the output during installation process.
2. Used AppCleaner to check installed applications, does not find any malicious app installed from Comcast installer.
3. Used pkgutil command to search for anything related to comcast in package receipt database. See pkgutil manpage for details how to use it. I could not find any new applications installed from this installer pkg.
4. Used Pacifist to check the content of the pkg file. Did not see much suspicious content except for several Ruby and shell scripts to run during installation.
Don't install Firefox Toolbar
By default, these website shortcuts are install on your desktop, remove them
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