It all depends which zig ( other makes are available
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) unit you go for,
I've got the same dilemma at the moment and I think I've settled on a zig cf9 (or maybe cf8) as it does everything I want from it, only downsize is that it's quite a large unit. Split charging is done by the unit but what I like is that it's also a battery charger for when your on a mains hookup, which is good as I can hookup when it's parked in the garage at home too.
Spec for the cf9.
ZIG CF9 Distribution system
Battery charging and distribution system.
- Conforms to current EMC and Electrical safety regulations and is CE marked.
- 240v to 12v converter for battery charging.
- 3 x 10A switched fused outlets.
- Battery condition monitor.
- Easy to install (fitting instruction enclosed).
- Split charging facility from engine.
- Fits aperature size 275mm (W) x 85mm (H)
- Mains 240v and fridge supply
- Colour: Brown
I'm holding out for a decent second hand one though as there not cheap at £200 and its not high on my list of needs at the moment.
Basically all the zig units are different specs so just do your homework before you buy.
I've also been looking at a more modern digital units as there more compact but a lot more expensive.
http://www.ebay.co.uk/itm/CBE-PC100...BATTERY-CHARGER-SYSTEM-12V-240V-/330759811433