Hey, Buy a Benz battery! Cost a little more but it is original and is very high quality, Interstate bat. are very good no doubt about it and probably so are the other manufactures. BUT, MB gives a 2 yr unlimited warranty on there batteries, no questions asked. Most others are "Pro Rated" which means if it fails you pay for the monthes the battery was in your car. They usually have it figured so to replace it for you is about the same price as a new one.
Keep it Benz! can't go wrong or..... You get what you pay for!