Given your budget I would go with the 90P option. I disagree with RW on the 3805 being able to drive the 100's. I use to own Studio 40's and drove them with a yamaha receiver with the same power rating as the 3805. The Yamaha couldn't control the drivers like a good quaility separate amp could even though they are a efficent speaker. It doesn't really matter though because I don't think you can find a pair of 100's for 1000.
Good Luck,
Burton
Good Luck,
Burton