Anyone Have Experience with Smart Chargers?

Gave myself a firm kick in the ass, because I discovered I had inadvertently unplugged my C-Tek Smart Battery Charger. I have a panel that serves all sorts of plugs I use in my study. I must have pulled the charger plug when trying to unplug my external photography monitor. I always unplug that after I use it. 

Charger could have been unplugged a day, or maybe a month. I keep the closed cell marine battery I use for my electric motor constantly on charge. When it slightly loses charge, the charger juices it back, so basically it's always fully charged. From what I read, that's what's best for it. I'm not very technical, so I don't remember specifics well enough to explain. 

Two-and-a-half years ago, I bought the same sort of Cabelas battery I previously owned. I used to just charge the old one before going out, and it lasted seven years. I bought the C-Tek for $107.00 and figure it's worth the money, if it adds a few years more than seven to the life of a $265.00 battery. I had to buy a new charger anyway, and that was a good thing, I think. 

Anyone have experience with smart chargers? Any stories of long-lived batteries? Please tell the story in the comments section below, if you do.