I just had my first semi short duration sears diehard platinum 31M failure (date code 12 2012). I first bought an Odyssey in 2004. It lasted 7 years and probably would have gone longer, but wife and I were away from home on a contract job, and reliability was key. It got replaced with an identical Odyssey. The first 31m was bought in Feb 2013.
I have owned a total of 3 Odysseys and 5 platinum diehards. I still have 2 Odysseys and 3 PDH. Assuming the PDH is internally identical as an Odyssey, i have been satisfied with both jbrands. I wrote about upgrading the wife's Sequoia with the 31m in the Toyota section. The sequoia started to behave strangely (clock memory/radio preset loss and a slight delay when engaging the starter). Obviously an intermittent electrical problem. Battery voltage indicated OK. It progressed to the remote door locks not working when approaching car, and an exteneded delay engaging the starter, then finally a condition where the starter solenoid would only click, and no start.
When i removed tehe positive battery cable, i noticed the positive post could be rotated very slightly, but still showed good voltage. Took it to sears where they declared battery failed. They replaced it for free and now i have a new one with a date code of 5. 2015.
What is interesting to me is, the battery was used as a voltage source for my ham radio in the garage and ARB fridge, all low amp draws, was moved very little, and was charged with an Odyssey Ultimizer. Not mistreated, just a few weeks in te Sequoia. It appears a some type of internal failure.