Soft Start Actual Reduction in Starting Current?

Adding generator connection to house so can use my RV inverter generator (upgrading generator currently so want to plan it out, but dont want to oversize because they get f***ing heavy). Looking at MicroAir soft start for my 3.5T Carrier condenser (17A RLA, 112 LRA). MicroAir says it reduces "up to 75%" but I know thats probably fluffed up for marketing. What is anyones real world experience in how much it actually reduces peak starting current?