Not sure how much increased space there is but these are not stock bags with extensions. They are carpeted with a little shelf in the bottom, you can remove the shelf to put items you don't use often such as tools (blah blah about the HD and tools jokes to ensue) etc...

The bike is lowered actually via an Arnott air ride setup.

I like the S curve because it keeps the bike from looking boxy. These bags are also unique to most as it has a line styled into the side that follows the flow of the battery cover, most aftermarket bags either have no line or just a straight line.

Top Shop is the company.