The studies I looked at showed no difference between the filtered and unfiltered in terms of side effects at any therapeutic dose. I didn't look at the drug company website for what it claimed, but I'm pretty sure that they were saying it was better and that that was what the doctor had seen. The filtered version was still patented, so of course they wanted it to be the version prescribed.

As far as I could tell, it didn't work less well than bog standard albuterol, but with the same probability of side effects, the price of trying it out didn't seem worthwhile, not during the decade plus when I had no symptoms. Does that make sense?