Hi Terry,
My professional experience with the Truecharge+ series ( the old yellow one ) has been very positive. They are still available online at attractive prices, and they will do a good job. The only "oops" with them was early in their production ( years ago ), they produced a whole bunch of them with the cooling fans wired backwards so that they were trying to
push air through the unit instead of
pull air through the unit, and this resulted in rapid failures. Other than that, they have been very good.
I have a new Truechage2 40 amp unit that I will fully evaluate and provide an update to my previous Battery Charger product review once Xantrex has the much-delayed remote panel available sometime next month. However, based upon the specs and limited testing, it appears that the Truecharge2 series will be generally very good, with possibly a few quirks that might earn it a low-level "WTF" comment.
Keeping you fridge running with the battery charger ON all the time will not "exercise" an smart battery charger like the Truecharge+ or Truecharge2 series of chargers, at least once the charger goes into the float mode. Once in the float mode, the Xantrex Truecharge_ series chargers will only initiate a full recharge sequence if the load causes the battery voltage to drop below about 12.5 volts for several minutes, OR once every 21 days. The low voltage re-trigger won't happen until the total load current significantly exceeds the rated capacity of the charger, which in the case of the Truecharge_ series will be either 20 or 40 amps. This won't happen with any of the small sealed compressor based systems that most of us have on our C34s.
The flip side of the argument is that your batteries will thank you if you don't leave them on a float charge for months and years at a time since this promotes positive grid corrosion ( i.e. - accelerated deterioration ) of your lead acid batteries. The alternative is to provide an AC powered DC power supply for just your 12v refrigeration system for when you are at the dock, and then use the battery charger to cycle charge your batteries when they actually need it. If you do a search of past postings, you will find the discussion I posted on how to do this, including where to get suitable parts. ( Stu, the "Search Master", can probably show you a link

) One of the Catalina owners even turned it into an article in the Technical Pullout section of the Mainsheet magazine about a year ago. If you can't find any of that, and you are interested in how to do it, just let me know and I can send you the information direct offline.
Regards,
John