I had 2 Balmar MC-614s fail on me (both out of warranty, of course). I switched to their ARS-5 and that has worked flawlessly ever since. So I would not waste my money on the more expensive MC-614. I would strongly recommend adding an alternator temperature sensor. I don't know what the rating of your Delco alternator is, but I had to limit the maximum output of my ARS-5 to about 90% in order to avoid burning up my Balmar alternator. The long display of the ARS-5 shows the actual alternator temperature. I am also a happy user of Yandina's battery combiner. I have no experience with the Xantrex echo charger. Another useful upgrade would be a battery monitor, such as the Victron BMV-600S.

Thierry