I have a Ctek charger and it's very good indeed.
Why don't you get a split charge relay fitted, my last one cost me about £120 fitted. Both my old vans had these chargers fitted and they were really good. Originally, I was against a SCR as I don't do many miles, so I thought they would be no good; on some days I would get to my first job and the engine isn't even warm! However, they both worked surprisingly well. I don't have one fitted in my current van (very long story) so I use the Ctek instead.
To sum up, Ctek very good, split charge relay (fitted properly) very good.
I do a lot of miles. My controller has a charging facility integrated in it. It shows CHG when I open the back doors after driving but it doesn't charge efficiently. My van has a braking system that doesn't allow charging, it's regenerative or something. Spruce will know what I mean.
Once you have regenerative braking, you need a battery 2 battery charger rather than a split charge relay.
With regenerative braking, the ECU reduces the alternator's charge output voltage to around 12v when the starter battery reaches 80%. This remaining 20% of capacity allows for a storage space for when regenerative braking is activated.
The trouble is that while this is waiting for regen to happen, your leisure battery isn't being charged.
A b2b charger will boost the 12v to 14.2v and charge the leisure battery even when the starter battery isn't being charged.
When regen does kick in, the voltage output is between 15 and 17v, depending on the vehicle. These voltages are too high for a lead acid battery. A b2b charger will throttle back this over voltage, so it remains at 14.2v.