I'm not totally convinced, the battery was charged for 2 days straight and driven 300 miles - Wouldn't that imply alternator or something causing the battery to not charge while driving?

The previous battery died and it was really obvious as the lights dimmed and the stereo was low etc. None of that is happening this time. It seems like full power but just not getting from the battery in the boot to the starter.

Also, the battery that did start it was a tiny little thing out of a 1.2 skoda... Car wasn't even started, just connected directly to the engine bay terminals.

Any other ideas?

S.