For those who power-sand , how do you approach sharp inside corners, such as at the bottom of a footed bowl? Do you use discs that match the backup pad diameter in order to get closer into the corner, or the larger discs that are typically used inside bowls to avoid digging in, and accept that there will be a wider hand-sanded area? Do you find any problems in finishing between the power and hand sanded parts?

For what it's worth, I use a close quarter drill for most sanding and a Grex random orbit for the final stage where possible. If I stop at 320 with the Grex I hand sand to 400.