I personally love my 1210. It’s great. I might be wrong so some one correct me if I am. The 1210 has more options in the long run. If you were charging the same battery on both the 1210 or the 610, by far the 610 would charge faster. The built in balancer is a good feature. The there are more options with the 1210 in the long run. I didn't think the time difference mattered as much as the options mattered. I also bought the LBA10 balancer. Great item too. I know I read somewhere here on the forums that there is another balancer same circuits, different stickers that had more connectors supplied with it. I can't find the name of it though.
same price but more connectors.