I have been using sears diehard batteries in all my cars for ages. If I buy a new car, as soon as that battery starts to get funky. (Normally 3-4 years in the south, georgia and florida). I replace them with diehard batteries. Only problem i have had with them is when i didn't clean the terminals. Apparently some corrosion in there will prevent charging, leaving you looking really dumb. Spent $70 bucks for a tow and a "cleaning" when i thought it was an alternator (different vehicle).
Now I use the whole thing. Felt washers, corrosion spray. I think I end up cleaning them about every other year or whenever I am doing any sort of maintenance where i need to remove the battery.