In case anyone's interested in trying such services, I just started free trials of Sling TV and Playstation VUE. The Sling package I'm trying is Orange plus Blue, which runs $40 for 44 channels. The Vue package I'm trying is the Core Slim, which runs $35 for 61 channels.
I've read Sling uses Microsoft Silverlight, but it was working even without it installed. So it either doesn't use it or their app doesn't require it being installed separately. Sling doesn't need to launch via a browser, so it may use it in it's own app. I'm not sure if Vue uses Silverlight, but the PC version requires launching via a browser, which IMO is less desirable.
IMO Sling wins on interface. It's much easier to navigate than Vue. It also wins on content. I not only get less channels on Vue, many of them that are supposed to be accessible say cannot be played outside your home, and I'm only using the service at home on my PC. I also had a recap of an NBA basketball game just suddenly stop playing. It wouldn't resume and the only way to watch it again was from the start, so I said screw it. Plus the tile for it shows the final score, which is something you really don't want to know before watching.
Performance wise I was expecting Vue to win, as most Sling vs Vue feedback I'd read leaned toward Vue having better IQ and less buffers, freezes and hitches. Sony also has a higher bitrate requirement, stating 10Mb download speed, vs Sling's 5MB. Since my ISP is 15MB down, I figured surely Vue will look better. At first glance, on TV shows and movies, Vue seems to have better IQ. It's main Achilles heel is it hitches constantly. Whether it was watching Blackhawk Down, or that NBA finals game (Cavs vs Celtics), it would have a noticeable hitch whenever someone moved fast. Plus the Warriors vs Spurs game I watched the day prior on Sling had better IQ and smooth motion.
Another annoyance of Vue is they insist you have cookies enabled and no adblockers, making you feel even more vulnerable since PSN has suffered major hacks in recent years. Sling on the other hand will even work with a proxy. This means you actually can pickup shows that are not specific to your area if you like. The only downside of that is the speed drops, so it can affect IQ. When I disabled proxy it suddenly looked pristine by comparison, even though my ISP speed only increased 1.5MB. For movies and a lot of TV shows, Vue has better IQ and doesn't suffer from black crush, which is a bit of a problem on movie channels with Sling, but the hitching Vue suffers is not worth it at all.
To be quite honest, I'm not sure either service in the end is worth it as used. If you put it up against say renting full season discs at Netflix of popular TV shows, there's no comparison. It also looks noticeably worse than HDTV broadcasts, especially 1080i broadcasts. I may try Sling again once I upgrade to a better TV (now considering a Sony XBR49X900E when price drops well below $1000). I'm thinking with Sling, Sony's excellent upscaling and processing might be able to make it look better. Ironically though, I'm skeptical it could do anything to improve their own streaming service, since it hitches so badly. That may be due to it being primarily designed to stream on devices vs PCs though. They only recently offered browser streaming on a PC, so I may have to compare the two again on a Sony smart TV.
Clearly Sling's interface and lack of detection and streaming glitches makes it far easier and more enjoyable to use though. No one wants to be told they don't have access because they're not at home, when they are sitting at home. Best case scenario, even IF a Sony smart device clears up the stream stability, they still need to work on content (or pricing) and the interface. I'm about to call Vue support just to give them some feedback and ask if they've noticed any disparity in stream quality complaints between PC and Sony device users. They definitely didn't try to hard sell me on buying a Sony device to use the service when I asked questions about Vue prior to signing up. However, while that makes me feel like they'd answer questions about browser vs device streaming honestly, their support people seem to be young kids that aren't too technically knowledgeable about the service.