Alternate voice chats?

I've seen some people use alternate voice chats, instead of roll20's. Is there a reason, or just personal preference?

Roll20 can be a pain. The whole website is a work in progress as they upgrade, streamline, upgrade, streamline. Skype, for example, tends* to be more stable and an always be considered ooc for the purposes of chat logs... not to mention the additional layer of support it adds to communication in general. Some people would rather use Vent, Teamspeak or something similiar as well - because they have their own private server with a much better hosting capability than any of the playerbase. Overall? Less drain on Roll20 or the players hosting the calls/chat servers.

Roll20 uses a webRTC voice/video client hosted by Tokbox. It's gotten a lot better than it used to be (back with Flash) but it still gives some folks problems. More to the point, alternate voice chat systems like Skype, Vent, Google Handouts, etc offer more features than the built-in tool. Things like Push-to-talk, volume control, streaming other audio for sfx and music, etc. that make 3rd party clients more desirable. The built-in chat isn't "bad", it generally works fine. You just get more out of other clients.

We have gone back from Skype to Tokbox, recently it has gotten much better and takes less resources than Skype.

I use Ventrilo with Roll20, instead of the built-in Tokbox application. The main reason is for the push-to-talk feature. I don't want to subject my players to all the background noise going on at my place, and I certainly don't want to hear theirs continually. I swear, one of my players sounds like he's at a subway station, judging from all the background noise everytime he keys his mic.

Side note; You can just click on your chat avatar in Roll20 to mute your tokbox. Not exactly push to talk toggle, but clicking it easy enough (and is the same thing you have to do in Google Handouts anyway)

In my experience the built in chat works just fine in recent times, was awful when i first joined though. That being said we still have some problems but that is usually related more to bandwidth problems as some of my players have poor connections. When things are running normally we can hear and speak fine. I've considered using other programs but the issues of bandwidth always raises its ugly pre-millenium head. I would urge anyone to try a variety of different options before settling though as just because one 'works ok' doesn't mean it 'works best' :)

Recently switched to Google Hangouts for the video feature. I found the video feature in Roll20 is very sensitive. The audio seems to be fine though. I am sure it's on Roll20s big honking list of things to do and over time it will get better.

Some of it's inertia, but the main reason I keep using external voice is for redundancy. No service is immune to outages, glitches, and the like, and having two independent communication channels on two different servers means that your group can typically keep in touch (or even keep going) when one of them goes down. If Roll20 goes down, we can keep talking (and maybe even keep playing) on Hangouts or Skype; if whatever we're using for voice goes down, we can use Roll20's chat to keep the game going (or to martial everyone to a different voice service).