When UltraViolet was first launched to the public it had a lot of problems. You needed multiple accounts to redeem codes. Some people couldn't login to their accounts at all. Some devices didn't have apps available right away, and it was unclear whether you would get a SD or HD copy with your blu-ray disc. Using flixster was cumbersome, and some codes would not redeem. Now, all of those problems have been fixed.
For more than a year, I only used vudu, because it was the only good streaming service for a long time. Lately some other UV providers have really been innovating in this space, and they deserve a look. Here is a short review of all the UltraViolet retailers I've used.
Vudu: Has the most availability of UV films, and the highest video quality, but usually has higher prices than other providers. Sometimes they have good sales. They sometimes have films in the incorrect aspect ratio, even when other sources have the correct ones. Their Disc to Digital service is the cheapest and easiest to use and recognizes blu-ray discs, when others do not. Their IOS app is good, but it just allows downloads for offline viewing. The sorting option on the website is pretty useful, but it is also needed in the IOS app. The parental control is limited to TV's and set top boxes, it's not available on the website or IOS app. The Android app is much better.
Flixster: Was the first to launch UV access, but their website was slow, especially with large libraries, and sometimes failed to load at all. Most of those issues have been fixed. Their IOS app is pretty good, and it now allows HD playback. Only service that allows deletion of unwanted titles.
Target Ticket: I like their interface the best. It's clean and minimal when compared to vudu's. I also like the playlists feature, multiple family member accounts, & parental controls. The only drawback is that the website takes some time to load large libraries. They've also had good sales so far.
MGO: The website was slow to load, and the interface was bad when the service first launched, but it is much improved. I like their cards feature that lets you group movies together. Soon they will start selling gift cards that let you gift individual movies to people. I also like that it is built right into the Roku, with no need to install an app. I say this one is easily my second favorite as far as innovation, and I picked up Depsicable Me 2 HD for $8 on Black Friday.
CinemaNow: They often have good sales, but not much else is going for them. They did have a working IOS app from the beginning.
UltraViolet has come a long way in two years, but we still need better ways to sort our libraries, to prevent having to scroll for a very long time to get through a large libraries. I'm looking forward to the Common File Format, the ability to delete UV films, and upgrades from SD to HD. At that point I'll be satisfied with UV. Oh, and of course, Disney and MGM need to offer UV titles.