Excellent choice when using a larger and heavier lens on the Canon RP, such as lenses with a large zoom, RF lenses from the L series, or EF lenses with the EF-RF adapter. Automatically, the camera sits much better in the hand and the weight of the lens is easier to control, as the little finger of the hand is no longer under the camera body but in front, helping with the grip. If you are going to use your camera with significantly lighter kit lenses, the use of the grip may not be necessary, but still, the experience is noticeably better.
The build quality is not something amazing, it is an extremely lightweight plastic accessory with the exact same finish and color as the Canon RP.
One thing to note is that it is an extension grip, meaning it extends the body of the camera downwards, essentially only assisting in horizontal (landscape) shots, and it does not accept additional batteries. Additionally, when someone is going to use the camera on a tripod, there is no need to remove the grip, as it also has a socket where the plate can be screwed in.
As for the negatives, the price of the grip is rather steep, which on the day this review is written, was at €75.