Going cheap on batteries is false economy, IMHO.
When stranded by a cheesy battery, will you be saying "well, at least I saved $30, so it was worth it..."
I suggest Optima spiral cell batteries, particularly for interior mounted ones. Exide also makes a spiral cell now which is supposed to be very good, and a bit less money.
They cannot leak acid, and can even be mounted upside down!
1986 300E 5-Speed 240k mi.