I have not yet equalized our batteries, but have had several Rvers recommend it and plan to do it soon. Equalizing charges at a higher rate which removes scale from the battery plates. However, a word of caution, check the water level after equalizing because the high charge rate can boil off water, if low top off with distilled water. I replaced the four 6v inverter batteries with Interstate GC2 RV-XHD in June of 2010 they are holding up well--see link below.
http://www.interstatebatteries.com/cs_e ... RV6Volt|3|
In addition, I replaced the 12v Chassis and Coach batteries with Interstate batteries. All are doing well.