Sometimes Tinseth can be almost twice as much as Rager. The formulas are all bad, so it's best to pick one and stick with it, understanding that there is more to the bitterness we perceive than isomerized alpha acids, and MUCH more than a poor deterministic approximation thereof. I use Rager, personally.
The Fiesty(sic) Goat Brewery est. 2007 & Clusterfuggle Experimental Ales est. 2009
Planned: sLambic II, Flanders Red II
Primary: Saison, Berliner Weisse, Dark Mild, sLambic I
Secondary: Orange Blossom Mead, Flanders Red I
Kegged: Fat Man Porter w/ 1469, Fat Man Porter w/ 005, Centennial Falcon w/ Conan, Centennial Falcon w/ Denny's, Barrel-aged Fat Man Porter, Belgian Dark Strong
Bottled: Flanders Red I