...has mostly been proven to be a little antiquated and less accurate way of calculating appropriate twist rates than is Miller. (caveat being that I certainly do not hold a degree in Physics)
For the lay person, JBM's calculators are probably the appropriate method. Used in a little more sophistication, and in conjunction with a spreadsheet, they will allow you to build a fairly accurate chart of what stability factors will be achieved across multiple sets of environmental parameters.
If anybody wants to be a student of it though, I still recommend you learn to do the calculations yourself, on real paper, with a real pencil.
That being said, as much calculation as you want to do, at the end of the day, unless your barrel manufacturer can deliver extremely precise and extremely accurate twist rates in the barrel you purchase, you can end up getting hosed anyway. This is one key differentiation between the barrels that "should" shoot (but don't), and the barrels that almost ALWAYS shoot. Choose carefully.
-Nate
It's not a little antiquated it's a lot antiquated. But, a place to start if one wants to put numbers on paper and do the calculations.
JBM is way quicker than doing it yourself. Also, as has already been mentioned. What will this rifle be used for? What meets the need, meets the need.