Wizz28,
I'm an electronics simpleton

... does the more amps mean an ability to run longer or being able to hook up more things to it , dew heaters etc.
Supercheap auto has the 900amp for $65 which seems really cheap! The 1900amp is $129... even better???? Good thread this one makes it simple.
Hey Brian, just added a 4" ED bought off the classifides

(thanks Lucas)Off course it's cloudy here but a quick try on trees no false colour...can't wait for the real stuff.
Cheers Matt