Alice, this is an excellent question, and something we cover in the Mastery Level Workshop on Advanced Pricing. It is also in the updated version of the Workbook, which is available stand alone.
Basically, the main advantages of using advanced pricing for the base price are:
1. All prices are in the same file, for reporting purposes.
2. The users only have to learn one interface for pricing.
I always use Advanced Pricing for my base price, except for certain circumstances where the Base Price file is the better choice. One example is if you need to base a formula calculation (such as a commision equal to (base price minus $25.00) * 1% on the base price, then you need the base price in the Base Price file.
I believe you already bought the workbook, and we are in the process of making electronic updates available and will let you know in about two weeks when you can download a fresh copy.