Bill,
This link was the best I could find so far about who the major manufacturers of batteries are for standard automotive applications here in the U.S.:
http://www.thebatteryman.com/battery_manufacturers.html Interstate seems to be conspicuously absent...
Here's another couple of links that are chock full of information on auto batteries:
http://www.batterycouncil.org/ and
http://www.dmoz.org/Business/Industries/Industrial_Supply/Batteries/
Optima is one brand that has been discussed here on the forum quite a bit. They are now owned by Interstate But their batteries aren't always a perfect fit in Mercedes cars.
Here's a tip on getting more battery for your buck. Find an Interstste distributor in your area, and buy direct from them. And when you do, ask them if they have any batteries in the model you need that are "Blems", or "Pre-Installs".
These units are every bit as good as the "brand new" ones, and come with the same warranty, but are sold for at least 25% less that the "brand new" ones.
BTW, if you want to know more about the antifreeze issue, a new member has dredged up the old Red vs Green thread, and I posted the link to Valvoline's website where they detail the Glysantin G 05 coolant...
[Edited by longston on 02-25-2001 at 05:45 PM]