I have the 2812, and while it works well, I would not buy it again. Mine is six years old at this point.
Mainly my gripe is 12v. I should have studied more and went with a higher voltage on the battery bank. The biggest issue is the difference between full and "empty". On a 12v system that's only 0.8 volts, not much margin. On a 48v system you have 3.2 volt difference to work with.
Also like Don said, no hybrid mode on the 2812, the 3012 is the newer model with the load support feature. Load support lets you run heavy loads on a small generator or weak shore power connection. It uses battery to supplement amps.
Victron has more bells and whistles, not sure what improvements they offer.