Yes, overall it's been very consistent for me. I've found that the strength of the GPS/satellite signal can vary in some locations and if the Dragy moves in the car during acceleration it can throw off the readings. One M3P Dragy user said that their Dragy fell off the dash and into the floor during a pass. It resulted in well over 1.0G of acceleration and their abnormally high record 0-60mph.
The specific new 1/8 mile record that you're referring to (7.18) is a bit suspicious because I've spoken to that user in the past and their acceleration times have consistently been similar or slightly slower than mine. There was no mention of modifications, weight reduction, etc. in this post whereas their past posts have stated the SOC & stock wheels/tires. Their past 1/8 mile runs were much higher at 7.37, 7.40, 7.41, 7.43, 7.38, 7.37, 7.35, 7.40, etc. On that same run as their 1/8 mile record, their 0-60mph also went to 3.14 from 3.34, 3.30, 3.26, 3.24, 3.27, 3.33, 3.35, 3.33, 3.27, 3.29, 3.24, 3.27, etc.
The suspicious thing on these best runs is that there's no temperature or DA (Density Altitude) reported. The user's peak G was also over 1.1G on this run and has consistently been <= 1.0G in past runs. I'm not saying the times are impossible, just suspicious given a single record run with no details provided and the temp/DA not being reported by the Dragy.
If the Dragy user is consistent with the ambient temps, run location, SOC/battery temp, Dragy mounting on the car, etc. then the Dragy & M3P will both yield very consistent times.