For me the Aston has totally transformed my car, Barley Mow has started a winter series and we are now 2 weeks into it. The same track will run for 4 weeks with the final on the last week.
On the 6th of Jan I ran the lotus shell and my times were not that bad. (results below Simon 1) 12.33 Best lap and 13.05 Average Lap
On the 13th of Jan the only real mod to my car was the replacement of the lotus for the Aston shell. My best time the first week was now higher than my average time for the race the second week. (Results below Simon 2) 11.37 Best Lap and 12.15 Average lap
For me the Aston is very similar to the speed 6.

I would expect to be quicker on the second week but a full 2 laps is not something that i was expecting!