There is a way around this.
My Panasonic EX79 has an option for over recording. You choose to have the record start 5, 10 or 15 mins earlier and later than the guide time, just look in your recording options of the setup menu.
I find that about 10 mins each way is good, but keep an eye on what show is before it. If it is a rubbish piece of poo reality show (like most of channel 10) then set the recorder to also record the TV show after the one you want. This keeps you covers you in the even they run the reality junk 30 mins late.
However, this does not work if you are recording shows on different channels back-to-back.
Cheers.