Previously I gave you my opinion of the AD&D/D20 system. Something involving testicles and rats if I recall correctly.
Evidently, Blogger runs links at the top of the free pages linking to items mentioned in the posts. It would also seem that the algorithms do not catch on well to context, because ever since I wrote that entry, the links have always included AD&D. If the D20 system works for you, more power to you (computing power, you'll need it).
As for me, I think I'd have to set the number of rats to at least four before I would use D20.