Sounds like I'm the only one, but I've not had good experiences with Interstate batteries. I've had at least four, possibly five, Interstate battery failures over the past 10 years in different vehicles. All the failures were due to a shorted cell - this causes the battery to show normal/full voltage with light load, but voltage drops to low single digits with any serious load (i.e., starter engaged). All the failed Interstates were wet-cell flooded (not AGM), all were Group 48 or 49 (or equivalent, like the 93), and IIRC all were roughly 3-4 years old.
I've been buying only AGM batteries now; I have a couple of factory/dealer Mercedes AGM Group 49's that are 12 and 14 years old respectively, and still going strong. (Those are trunk-mounted away from engine heat, which probably helps longevity.) AGM's cost more up front but IMO tend to have better reliability, lifespan, and I like the safety aspect with no concern about leakage or explosion hazard. When the current battery in my LR4 finally dies I'll be looking for a Group 49 AGM to replace it.
Related anecdote: I have a PowerPulse desulfator installed in a number of my vehicles, with both standard flooded and AGM batteries. Most all of them have been seeing 10+ year battery life.
Click here for more info. Now that batteries are $150-$200 for AGM, if a $40 desulfator can extend the life a few years, IMO it's worth it. Be warned that the PowerPulse uses some battery power to function, if the vehicle will be parked for more than 2-3 weeks, you MUST put it on a trickle charger / maintainer or you may find a flat battery a month later. Even without a desulfator, a trickle charger is still a good idea if parking for 3+ weeks...
