I just replaced the horizontal manometer on my Simons Carb Comparator. I bought a different model Dwyer 40-2 vs 40-1. Dwyer specifies their blue oil vs the red oil. I noticed that the blue oil has double the specific gravity then the red. Will the higher specific gravity make it more difficult to see small changes? Obviously I really don't care about the accuracy of the numbers but only consistency and being able to determine if a change is good or bad. What do you guys think?