I got one of the series on a Kindle Deal a while back, but they tend not to appear as deals on the UK store. We seem to get mostly chick lit or family sagas
For my part I'd say they are worth buying on a deal, but not necessarily full price. They're police procedurals but more
Dixon of Dock Green than
Hill Street Blues, i.e. cosy not hard boiled but with a distinct weird flavour to them. If you want the weirdness (urban fantasy) ramped up a bit, Ben Aaronvitch's Rivers of London London series is very good (and they seem to turn up quite frequently on deals), although be warned you may need to get a lexicon of British cop slang.