The X9 has has 3 different versions with slightly different specifications. There are various battery specifications covering 2 different motor sizes.
If you are having difficulty in deciding on what version to go for then have a look at the specification chart and then decide what is the most important factor for what you are looking for from the X9.
For example if you're looking to use on a hilly route then a model rated at 30° would be more important than the range.
But if range, and not having to charge your scooter so frequently is of prime importance then you may want to opt for a model that has a 100km range over the 75km range model.
If you need to carry the scooter upstairs then you may consider the 1kg weight saving in certain models may be the most important factor. However if you're looking for a scooter that's even more suitable for portability and light weight then it may be worth looking at the X8 or X7 Pro as these models of scooter are more light weight.
And finally there is the budget. If you're working to a budget then the price may be the over riding factor in selecting the scooter.
With many factors being the same, max speed, brakes, size whatever scooter you opt for we're sure you'll be delighted with your purchase.