Well i started this topic just to ask about some models. I , for example, i will use the scooter to get to some dive sites.
1. I don't have a boat
2. I don't want a boat right now.
3. The dive sites are about 1 km from the shore.
I have a lot of dive sites like these and i can't get to them by swimming with all my gear with me. So yeah, it's usefull in some situations . I don't care if i look BEAUTIFULL with it. I just want the job done.
A km is a long way. I have sites that are 1/2km from shore and I'm reluctant to do them with my scooter. We used to do longer dives in Banff but that required pretty beefy scooters for the time (gavins with magnum hull or the X-Scooter echo with the long hull and extra batteries).
One important question is this: is it possible to swim the entire 1km home from the site if your scooter dies? If yes, buy one that's good for the 2km total journey. If not, you need a backup scooter as well. Double the cost. Some may say you can count on your buddy to bring you home on their scooter, but don't. Have at least one spare in that case.
Otherwise, you are looking at something that should have 2km plus reserve in it's range. If you use rule of thirds, you need a 6km scooter. If you can swim part way, then maybe rule of halves and a 4km scooter. Either way, that's a serious scooter range.