I've had a NOCO Gen2 20 amp for about 4 years and love it. The 20 amps is overkill for me, as I rarely fish back to back days. But it does charge up my 2 group 27 batteries quickly. I should've saved some $ and went with the mini, which would have also saved me a bit of space. But no complaints. I'm sure most "smart" chargers are similar, but the NOCO is more then just a charger. It also maintains battery charge without overcharging, optimizes internal battery chemistry to increase performance/longevity and can even restore some of a batteries lost capacity. Other then checking the water in my batteries from time to time I just plug in my NOCO when I get home and my batteries are charged and ready to go the next time out.
I also had a lighting strike 2 years ago that killed the one bank on my NOCO (among other electronics in my house ), but didn't harm the battery that was connected to that bank. Not sure if the NOCO protected the battery or not, but either way it wasn't harmed. And NOCO replaced the charger free of charge. Great customer service in my experience.