I never buy cheapo batteries, although you can be caught out by fakes.
I have had Duracell batteries leak and cause damage to my wall clock, the battery was well in date, but leaked from the negative end ruining the contact spring, luckily I managed to repair it.
I have had similar problems with Sainsburys own brand batteries as well.
I have used Energizer batteries for the last two or three years with no problems, I will stick with these.
Mark