Best brands when it comes to the alps

[Double Deuces]

Why are mylans "bottom of the barrel"? Are there lab tests that show mylans contain less than what they claim(if so I'd love to see them because I haven't yet)? Ive tried a VERY wide variety of alps from Upjohn and Gaders to those "bottom of the barrel" mylans and if they are legitimate they all work fine for me. No "dry humor" here, just an honest opinion. 

-DD