Is the only difference between the regular and the Plus the composite bit and the $100 price tag?
There are a couple different options and price levels (retail price)
10"
Alpha (steel bit) and one battery
579.99
10" Alpha Plus (composite bit) and one battery
729.99
10" Alpha plus (composite bit) and 2 batteries
799.99
Essentially yes, the bit material is really the only difference between the Alpha and Alpha Plus