I'm actually warming to UV mainly because you can use it with so many different services and devices (my Apple TV being the notable exception). I think the main problem in the UK is that we can only access our UV films through Flixster who are improving but still aren't great. I already use a dns service called unblock-us to acces Hulu plus and US Netflix and recently discovered I can also use that service to access Vudu and stream/download my UV collection through them instead.
The difference in the experience I've had with vudu compared to flixster is phenomenal. The movies stream and download flawlessly on my iphone, ipad and pc. I still can't use my Apple TV so in the living room I use vudu to stream to my xbox. Their HDX format is very high quality, close to Blu ray IMO, so the movies look great on my big screen.
Vudu gave me 10 free SD movies (not an amazing selection but worth the zero pounds i paid for them) for creating a new account and linking it with my existing UV account and $5.99 store credit for using their xbox app.
I used the the store credit to rent an HDX quality film and was again impressed. Lastly, I was able to try their in-home disc to digital service which is currently in beta. I stuck my Pulp Fiction DVD in my PC, gave vudu $5 and they added an HDX copy of Pulp Fiction to my UV account.
I really WISH iTunes would support UV but I don't see that happening so for everyone else not enjoying UV with flixster I recommend trying Vudu.
Ps Vudu aren't paying me for this post, honest!