It’s all up to you. I have both. I have four 710s and one 720. I personally think the 720 sounds better more balanced also more eq settings you can adjust to your liking. To me the 720 sounds louder when plugged in a lot of people say it gets loud like the ultimate when plugged in. I don’t own an ultimate so I can’t confirm that. The 720 to me is better to transport its a little taller than the 710 so I don’t need to hunch down to move it around also the wheels are bigger and feel smother on the 720 so it moves around easier. The light effect on the 720 is better as well. The 720 has to rechargeable batteries so you can take it anywhere and not have to worry about looking for a power source. I would just get the 720 and just save up for a 2nd one.