I've had an Elgato TV tuner stick attached to my iMac and before that to a Mac Mini for a couple of years. But last week I upgraded to the new Elgato Diversity which, despite being little bigger than a USB memory stick, contains two separate tuners so you can record two programmes at the same time.
The updated software now includes a form of series link so you can automatically record every transmission of a particular show. There's even a setting to get the tuner to ignore repeats. So far, everything has worked well and I am building up a store of shows which I can copy to my MacBook Pro for when I travel. Another useful benefit is the free year's subscription to the German programming guide, tvtv. I've subscribed for a number of years and found it useful. When away from home you can access the tvtv site and tick off the programmes you want to record. Every hour or so the Elgato software on the home computer checks for updates and adds any requests to the schedule. Last, but certainly not least, the Diversity transforms my 24in iMac into a fully fledged television with all the facilities you'd expect from a dedicated set. Buying the Elgato Diversity has stopped me from upgrading my Humax HDD recorder which, with its 160GB disk and annoying clicking noise, is nearing the end of its life. I now feel confident in using the Elgato system which brings greater flexibility, particularly in choice of disk storage and the ability to back up and copy programming.