I am also surprised at all the negative comments. I've had lovefilm for a good 18 months and love it! We used to have the three disc unlimited package but a while ago reduced to 1 disc at a time, but with unlimited online watching (£9.99/month). We don't have sky so this suits me perfectly, especially because our tv now hooks up directly to lovefilm and we can watch all the online available films (literally thousands, I am not joking) straight on the tv (Playstations also have this function).
In all the time I've had discs coming to the house, I think I've only had two scratched discs. Each time I was given the option to have the same film sent out to me again or to have a different one off my list. This was in addition to my normal disc allowance. I sorted it out online very easily and have never needed to call the company. I can also cancel my subscription online and have friends who have done that when they wanted a break.
As for the disc turnaround, it is super-fast. If I get a disc in the post on Monday, I'll get a new disc delivered back to my house on Wednesday. The only time this was delayed was when the post was on strike and when it snowed so much the mail couldn't get to us.
I love that I can get foreign movies that would not normally be available to me, but can also chillax at home when I'm stressing and watch as may chickflicks as I want.
The online library is growing so quickly and we have been promised that soon there will be tv shows available online, too (very similar to Netflix, which is the US version of Lovefilm). I can't wait to have access to Blackadder or the IT crowd whenever I want it
If you do decide to go for the free trial, then what you need to do is make sure you make your choice of package clear before the end of the trial (you can set it online - very easy) and return any surplus discs before the end of the month. So, if you take the free trial and choose three discs, but when you start paying you only want to have one disc at a time, select your package online a couple of days before the end of the month and make sure you don't have more than one disc at home or still in the post. Otherwise you will get charged the three-disc package fees. I think that's only fair.
I'd say it's worth a try.