Grouping

I would like to know the difference in grouping between an Airforce gun (condor) without a regulator and then with a regulator. Is there a noticeable difference?
People with regulators installed can you please tell me how much it improved your gun as to before and after adding a regulator.
I want to improve my accuracy and consistency of my Condor .177 since I see a pretty big difference between Theoben and HW100 guns at my shooting range even though i tried most the thing on this forum. Im not saying im expecting that kind of accuracy but i want to be closer and i am hoping a regulator can help me achieve what i am looking for.