Choosing an ikebana container can be tricky. Best container for you depends on the school and level you belong to and your sensei's style.
Kathy and I am a potter who makes containers for all levels of experiences in most schools. The suggestions I write here are from our perspective as a container maker and with our at most respect to each schools and senseis.
Prospective ikebana students: if you haven't found a ikebana school for you, we suggest first find a "sensei'' (teacher in Japanese). I would suggest going to Ikebana International North & Central American Region (NCAR) or regional Ikebana International (I.I.) in your country. At the website, you will find chapters all over North america. There you can find a chapter near your home.
On the regional I.I. chapter website or their social media page, you will find images of arrangements made by your future senseis. There are lists of teachers on the sites or you can contact your local I.I. chapter to find a teacher.
Beginner ikebana student: if you are looking for your first container, you should definitely consult with your sensei first. What you may find an entry-level container may actually be for advanced levels.
You can share our "new student container page" with your sensei and ask her suggestions.
As we made ikebana containers for 10 years, we learned that it is wisest idea to consult with each school's sensei to produce containers. Only sensei knows every level and style of arrangements of their school. And they also know the usability of containers from not only their experience but through the eyes of every level of many students they have taught. So your sensei is the only person you should listen to.