Enterprise voice in the cloud
I've used Skype Business (name change from Lync) in two companies. In one of them I was introduced to it as, "problematic." Now, having used it for months, multiple times a day for video, voice and chat, I never had a problem with it.
Voice calls - great quality if it was with someone in the same building or half way across the globe. No fuzzing or dropping.
Video calls - same. Great quality. No big drain on the computer so I could do other things. Again, good quality for the same building or globally.
Chat - what to say here apart from, it worked. Chat is a nice feature if you want to keep a history of messages.
Meetings - we managed to get +10 people, all from various locations, on different systems, using varying bandwidths, some connecting via Skype/Skype for business/mobiles, landlines. Only 1 person had a problem and that was due to their AD FS set up. We had video, audio, and chat. We transferred files. Some of us switched to muted mics just to listen....
Some people have had sign on issues but I think that may be more to do with internal set up because my experience hasn't included this.
Security and features that I used/like:
Skype For Business traffic is encrypted using TLS
You get archiving of messages
P2P file transfers
IM and conferencing
HD 1080p available depending on plan
Ability to have a presenter for training or to chair meetings
You can record content
Meetings can be scheduled via Outlook
The thing I want from any app is this: it needs to deliver. For me, Skype Business did. Does it take a bit of work to integrate into systems? Well, I've yet to meet a bit of kit with more than three features that doesn't. Is it worth it? I believe so. Skype for business is convenient. It's one of those things that's there, you use it, you forget about it - we're all happy. (or, at least, I was)