The USP is a polymer-framed hammer-fired combat pistol.
The grip is completely fixed and offers no adjustment.
The trigger group is highly configurable and can be configured as DA/SA, DAO, LEM, as a target/match trigger, with or without a decocker or safety, or as certain combinations thereof.
The pistol predates picatinny rails, but it has a proprietary rail. Dedicated lights/lasers are somewhat available. Picatinny adapters may also be used, although they drop the light/laser fairly low on the gun.
The VP9 is a polymer-framed striker-fired "budget" civilian's pistol.
It has a highly ergonomic and configurable grip. There are three sizes each of backstrap, left grip panel, and right grip panel.
It also offers "charging supports", which are little plastic tabs that protrude from the slide serrations to offer a more positive grip. They are kind of a silly but effective (and removable) feature.
It only has one trigger option: a fairly decent single action type trigger with no external safety, complete with the always fashionable trigger dingus.
It has a standard picatinny rail.