A jump cue is designed to make it easier to bounce the cue ball over an object ball and hit the target ball. It is shorter and light weight when compared to a regular cue. And it does make a jump easier and more controllable.
When a shooter decides to jump a ball (some pool halls forbid this and masse shots), the stick must be significantly elevated and precise force applied to drive the cue ball into the table and force a bounce (the height and distance are dependent on controlled speed and cue ball contact). If the venue that you play in allows jump shots, you may want to invest in a good jump cue.
Keep in mind that you must still learn how to control the jump, in height and distance and speed. If you are willing to spend a few months working on jump balls for about 20 minutes a day or so, then you should get one. If you are good at kicking to rails to make contact with the required object ball, or you don’t want to invest the time at this point in your shooting career, put the money into a spare shaft.
Several cue manufacturers make a combination break and jump cue. You will need to try these and see if they meet your requirements.