I was a proponent of blowing out the lines for a number of years. After about 10 successful years using that method, a few years back in the spring I had a cracked fitting (90deg elbow if I recall correctly) behind kitchen drawers. Wasn't a huge problem, but cost me a couple dollars for the new fitting, and a few hours (finding the problem, going to store for part, etc).
Since then I've been buying a few gallons of pink stuff when it's on sale each year. Doesn't take any longer than blowing lines out did, probably shorter since I used to let air run for a while to ensure I'd atomized it all. Also no longer concerned about what contaminants the air compressor introduced in our water lines. Side benefit is I can easily winterize on the road when heading back into freezing temps.
Good luck with whatever method. I think air alone is pretty good, but my experience suggests it still failed for me 10% of the time.
