but I will say somehow if the person is older using the
scooter there seems to be a little more compassion. In our case, we have never had any rude comments or whatever and we've done it over 10 times with a scooter. We don't try to be commandos with one, either. We are very watchful of other guests and we always yield. It can help to have the family around the scooter while mom is driving; so, others don't get too close.
A 3 wheeler will turn easier (easier for ride queues), but they can be a little (and I mean just a little) tipsy if you are going fast around a corner, for example and so forth. There's no real issue with them; unless, you get carried away and use it incorrectly. You have speed control on them. I'll never forget seeing some young adults in a group doing the Food and Wine festival with scooters. It was obvious they did not need scooters and they were getting drunker and drunker making their way around all the F/W festival booths. We watched them for a while. I believe it was dangerous for anyone close to this group with scooters. We almost saw one tip over. This is how scooters get a bad reputation. We were disgusted with this group.
The 4 wheeler is more balanced to a degree; so, many feel they are more stable. We've done both and I would have to agree with this, but we really don't have any issues with a three wheeeler.
Weight does play a significant roll on the size of the scooter; there are limits involved. Also, comfort is involved. With a bigger scooter there's more room for your legs and usually a better seat. A bigger scooter is a little harder on and off the buses and ride queues and so forth. If you are using your car for transporting a scooter then make sure it can break down into parts. A bigger scooter is obviously heavier. A bigger scooter has a longer lasting battery. It's advisable on all scooters to shut them off when you are standing still like with a show, parade or fireworks. Take your scooter key when you are parking it like for a meal.
Going to a local zoo is great practice with a scooter. You can also test drive a scooter at a local mobility store. Go to more than one mobility store to check it out more. Some of these stores will have the exact scooter that Apple rents out. The free grocery store scooters and so forth are all right to get in some practice, but the scooters you rent are easier to use; so, don't get discourage using a store one.
You may have to help your mom and do some of the harder scootering for her. Parking the scooter on the bus can get tricky. On and off the lift of the bus can be tricky, too. Luckily, normal protocol is you are the first one on the bus, but the last one off. You may have another scooter or wheelchair boarding with you, too. Some bus drivers are kind and some are not, most are kind. There are some other instances where I might do the scootering for her. For example, to get down to the Soarin' ride in the Land Pavilion you need to take the scooter on and off an elevator to get it to the proper level. I think it might be better if someone else did this part. Also, this pavilion is very crowded almost all the time. Some will park their scooters in this Land pavilion and walk around instead. The trek to get to Soarin' is a very long one; so, I wouldn't advise walking for this ride. You may find it better to skip this ride; although, I think it's a fun ride. You somewhat have to learn to be more patient using a scooter.
It's probably advisable to get some practice in at the resort with a scooter before going to the park. Build up confidence about it. If she is having difficulty then you need to help more with the hard stuff. Again, you need to be patient and not expect your mom to be a pro at it and help with the tough stuff.
If worse comes to worse, you may have to consider doing a wheelchair. My mom never learned how to drive and there were other issues, too like Alzheimer's and so we used a wheelchair for her.
I think you will be fine; just do your homework, now.