Super Large is a comfy fit on most 2 or 3 year olds. Imse Vimse does not fit like a balloon, as some do. They are not so super-snug that you can't get them up and down, either. They are just right.
These are called training pants, but they should really be called "first underwear". These are for a toddler or preschooler who really is going potty. They are great to fully catch accidents in most cases, keeping pants dry. Accidents are to be changed immediately. Don't expect any training pant to "hold it all in" for extended time periods. They are intended for daytime use, not nap or night. If you need that kind of protection, please choose a cloth diaper. These are not diapers. So if you are looking for an easy on, easy off diaper, you are looking for all-in-ones. Or for an in-between option, try putting a Bummis The Pull-On cover over the Imse Vimse Training Pant. That makes an accident not need to be changed immediately because the cover is waterproof, but it still functions pull-up, pull-down training pant. You only need 1 cover, if you need it at all, because you can re-use it many times between washings. We will say it again. Training pants are not diapers, they are first underwear. There is cotton inside for absorbency, then a waterproof layer, and soft cotton outside. The cotton is organically grown and soft and lovely.
For a true training pant, these Imse Vimse ones are the the best. They are very easy up and down, even over shoes. They are thick enough to catch what they might need to, but thin enough so that they don't feel like a diaper. This helps your child remember that he or she has underwear on. They are cotton on the outside, a waterproof PU laminated polyester(diaper cover fabric) waterproof layer and beautiful, soft unbleached cotton terry inside. The waterproof layer is hidden between the cotton layers so you can't touch it or feel it but it does provide protection for stopping the flow. But it's not a diaper so don't expect diaper-like containment and is not intended for overnight use (yes I am repeating for emphasis). Accidents must be changed immediately. A full-blown large pee accident will probably not hit the floor because of the trainer but I would expect to change the pants. Light or small pee accidents should be contained if changed promptly. These are perfect for learners to tend to start to pee, stop and run to the potty. Some children will go right from diapers to underwear, but sometimes it's nice for early learners to have some extra insurance built into their first pairs of underwear. I think these are especially useful for kids who train very young, and also for older kids who tend to be too busy to always remember to go potty. I used these during the potty learning time for my daughter. Then after she had day-trained, I continued to use these for many months on occasion, such as traveling or long car rides, or times when she might fall asleep in the car (she was not dry during sleep yet), or shopping trips, or if her grandparents were babysitting and she might not be as likely to tell them she had to go potty quickly enough. I like them just to have that extra insurance, even though most of the time it turned out to not be necessary. Having her in a training pant at those times helped me be more relaxed about it since she was still so young. And she considered them just another pair of underwear since they are so comfortable and not bulky.
They really help make the post-training months more relaxed and easier for both you and your child.
Great for EC.
Keep in mind baby's shape and legs. Big rounded "girl bottoms" need a bigger size. Tiny "no butt" boys might need to size down. Average shapes can order by the age recommendations.