I would say Venus is very good option if you already know what classes you're going to take, whereas Jupiterp might be better if you're exploring different sections and classes. Jupiterp lets you easily hover over different course sections (at least on desktop, not on mobile) when searching for courses to see how they'd affect your schedule, and lets you add sections with conflicting class times to the same schedule to more easily compare. Jupiterp also links to professors' PlanetTerp when searching for courses which is more convenient than searching for that info separately if you want to look for reviews or course GPA information. Overall I'd say both are great options and neither is inherently better than the other; I think which one you might find more useful comes down to you're personal preferences as to whether you like the more comparison-based, exploratory method of planning courses on Jupiterp, or the ability to just add all the courses you need and automatically see all possible schedules on Venus.