Well worth it
If you have a Gaia, this editor is a must have. Easy to set up and use, it allows much more detailed tweaking of the sound than the controls on the synth will. Allowing a precise tempo to be set, rather than just tapping it in, is an especially useful feature for the arpeggios, LFO & effects sync. Also useful for deconstructing patches to see how they are put together, so it's a learning tool as well. Another useful feature is the step-by-step guide to what you are actually programming, which you can print and save for reference.
Whether you are new to synths, or an old hand, this software really helps you get much more out of the Gaia. Highly recommended.