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: Fat Man Porter, Orange Blossom Mead, sLambic I
Secondary: Flanders Red I
Kegged: 3 different ciders, Janet's Brown, Barrel-aged Stout, Hallertau Blanc Pale Ale
Bottled: Flanders Red I