I can't comment on the Vicron product, other than to agree that they have a good reputation, but I use
this one from ABR-Sidewinder. There are a lot of decent dual battery controllers on the market but the thing that appeals to me the most about the ABR unit is the jump-start facility. I have a pair of deep cycle batteries under the rear tray and it's impossible to get to their terminals while the tray deck is screwed down. I have a switch on the dash that allows me to engage the jump-start facility of the controller. This proved especially useful when the cranking battery became end-of-life and wouldn't start the car any longer. Just flick the switch, start the engine and head down to the battery shop.