As someone that travels & rents cars frequently - I would recommend avoiding Advantage at all costs. I have intentionally used different providers and can honestly say that Advantage was the worst experience by far!
The customer service was horrible, the experience was unpleasant, and the up sell on the insurance was unlike anything I have ever seen. At one point, the 3 desk associates were all arguing with customers about why their insurance was not sufficient and advising that it was law that they needed to purchase additional liability insurance. This exercise in itself led to a 30 minute wait just to get my turn for the high pressure sales technique. Declined liability after 5+ minutes of being 'informed' of the repercussions of my decision and finally got my car... The car was OK... The Experience was not.
Will pass on Advantage in the future.