The Trimetric does a far better job than the Renogy monitor. That said, I prefer the Victron units, either BMV-712 or "Smart Shunt".
If you absolutely need to know the exact amount of battery capacity remaining, Renogy unit won't do it. Close, maybe, but no real cigar as it uses too many 'general assumptions' in the algorhythm that calculates SOC/DOD.
It's probably OK if one is only drawing a SMALL amount of current that remains steady. Varying high and low draws, for example a furnace cycling on and off over the night, can yield noticeable errors which the Renogy unit just "excuses" when the battery is fully charged again and the monitor resets to 100%
