I got £80 out of them in 4 weeks (4 missed appts for the same job). All that you have to do is ring them up, once you've selected your geographic area press #3 and utter the words "I wish to make a complaint!" The guys up at Speke are well used to it. They told me the last time that there's a 2 month waiting list for the vouchers (it isn't cash, you get vouchers that you can spend in certain stores) because they're having to issue so many. But then, the workmen who have come around have said that they used to get scheduled for 5-6 jobs a day, now they get upto 14 which they have no hope of completing. IE they know they're not coming as soon as they issue the day's work roster in the morning!
Happy days!